Don’t merge Etc/* with location-based names

The previous patch merged Etc/* names with location-based ones;
for example, it made Asia/Bangkok an alias for Etc/GMT-7.
This may have been a step too far, for reasons discussed here:
https://mm.icann.org/pipermail/tz/2021-May/030109.html
Revert that part of the change, by undoing the problematic merges.
* NEWS, theory.html, zone.tab, zone1970.tab:
Document the partial reversion of the recent merges.
* africa (Africa/Abidjan):
* asia (Asia/Urumqi, NBorneo, Asia/Kuching, Indian/Maldives)
(Asia/Riyadh, Asia/Bangkok, Asia/Dubai):
* australasia (Pacific/Gambier, Pacific/Tahiti, Pacific/Tarawa)
(Pacific/Palau, Pacific/Port_Moresby, Pacific/Guadalcanal):
* southamerica (America/La_Paz, America/Cayenne)
(Atlantic/South_Georgia):
Move from ‘backzone’ back to here, and remove the corresponding
‘backward’ links.
* backward: Don’t link from Etc/* to a location name.
* backzone: Above data moved from here.

1 files changed, 16 insertions, 16 deletions

diff --git a/zone1970.tab b/zone1970.tab
index 8cadd48..a02d94d 100644
--- a/zone1970.tab
+++ b/zone1970.tab
@@ -34,7 +34,7 @@
 #country-
 #codes	coordinates	TZ	comments
 AD	+4230+00131	Europe/Andorra
-AE,OM,RE,SC,TF	+2518+05518	Etc/GMT-4	UAE, Oman, Réunion, Seychelles, Crozet, Scattered Is
+AE,OM,RE,SC,TF	+2518+05518	Asia/Dubai	UAE, Oman, Réunion, Seychelles, Crozet, Scattered Is
 AF	+3431+06912	Asia/Kabul
 AL	+4120+01950	Europe/Tirane
 AM	+4011+04430	Asia/Yerevan
@@ -44,8 +44,6 @@ AQ	-6736+06253	Antarctica/Mawson	Mawson
 AQ	-6448-06406	Antarctica/Palmer	Palmer
 AQ	-6734-06808	Antarctica/Rothera	Rothera
 AQ	-720041+0023206	Antarctica/Troll	Troll
-AQ,KW,SA,YE	+2438+04643	Etc/GMT-3	Arabia, Syowa
-AQ,FM,PG	-0930+14710	Etc/GMT-10	Papua New Guinea (most areas), Chuuk, Yap, Dumont d'Urville
 AR	-3436-05827	America/Argentina/Buenos_Aires	Buenos Aires (BA, CF)
 AR	-3124-06411	America/Argentina/Cordoba	Argentina (most areas: CB, CC, CN, ER, FM, MN, SE, SF)
 AR	-2447-06525	America/Argentina/Salta	Salta (SA, LP, NQ, RN)
@@ -76,11 +74,9 @@ AZ	+4023+04951	Asia/Baku
 BB	+1306-05937	America/Barbados
 BD	+2343+09025	Asia/Dhaka
 BE,LU,NL	+5050+00420	Europe/Brussels
-BF,CI,GH,GM,GN,IS,ML,MR,SH,SL,SN,TG	+0519-00402	Etc/GMT
 BG	+4241+02319	Europe/Sofia
 BM	+3217-06446	Atlantic/Bermuda
-BN,MY	+0133+11020	Etc/GMT-8	Sabah, Sarawak, Brunei
-BO	-1630-06809	Etc/GMT+4
+BO	-1630-06809	America/La_Paz
 BR	-0351-03225	America/Noronha	Atlantic islands
 BR	-0127-04829	America/Belem	Pará (east); Amapá
 BR	-0343-03830	America/Fortaleza	Brazil (northeast: MA, PI, CE, RN, PB)
@@ -126,17 +122,17 @@ CA	+6043-13503	America/Whitehorse	MST - Yukon (east)
 CA	+6404-13925	America/Dawson	MST - Yukon (west)
 CA	+4916-12307	America/Vancouver	Pacific - BC (most areas)
 CH,DE,LI	+4723+00832	Europe/Zurich	Swiss time
+CI,BF,GH,GM,GN,IS,ML,MR,SH,SL,SN,TG	+0519-00402	Africa/Abidjan
 CK	-2114-15946	Pacific/Rarotonga
 CL	-3327-07040	America/Santiago	Chile (most areas)
 CL	-5309-07055	America/Punta_Arenas	Region of Magallanes
 CL	-2709-10926	Pacific/Easter	Easter Island
 CN	+3114+12128	Asia/Shanghai	Beijing Time
-CN,AQ	+4348+08735	Etc/GMT-6	Xinjiang Time, Vostok
+CN,AQ	+4348+08735	Asia/Urumqi	Xinjiang Time, Vostok
 CO	+0436-07405	America/Bogota
 CR	+0956-08405	America/Costa_Rica
 CU	+2308-08222	America/Havana
 CV	+1455-02331	Atlantic/Cape_Verde
-CX,KH,LA,TH,VN	+1345+10031	Etc/GMT-7	Indochina (most areas)
 CY	+3510+03322	Asia/Nicosia	Cyprus (most areas)
 CY	+3507+03357	Asia/Famagusta	Northern Cyprus
 CZ,SK	+5005+01426	Europe/Prague
@@ -159,14 +155,14 @@ FO	+6201-00646	Atlantic/Faroe
 FR,MC	+4852+00220	Europe/Paris
 GB,GG,IM,JE	+513030-0000731	Europe/London
 GE	+4143+04449	Asia/Tbilisi
-GF	+0456-05220	Etc/GMT+3
+GF	+0456-05220	America/Cayenne
 GI	+3608-00521	Europe/Gibraltar
 GL	+6411-05144	America/Nuuk	Greenland (most areas)
 GL	+7646-01840	America/Danmarkshavn	National Park (east coast)
 GL	+7029-02158	America/Scoresbysund	Scoresbysund/Ittoqqortoormiit
 GL	+7634-06847	America/Thule	Thule/Pituffik
 GR	+3758+02343	Europe/Athens
-GS	-5416-03632	Etc/GMT+2
+GS	-5416-03632	Atlantic/South_Georgia
 GT	+1438-09031	America/Guatemala
 GU,MP	+1328+14445	Pacific/Guam
 GW	+1151-01535	Africa/Bissau
@@ -191,9 +187,9 @@ JO	+3157+03556	Asia/Amman
 JP	+353916+1394441	Asia/Tokyo
 KE,DJ,ER,ET,KM,MG,SO,TZ,UG,YT	-0117+03649	Africa/Nairobi
 KG	+4254+07436	Asia/Bishkek
+KI,MH,TV,UM,WF	+0125+17300	Pacific/Tarawa	Gilberts, Marshalls, Tuvalu, Wallis & Futuna, Wake
 KI	-0308-17105	Pacific/Enderbury	Phoenix Islands
 KI	+0152-15720	Pacific/Kiritimati	Line Islands
-KI,MH,TV,UM,WF	+0125+17300	Etc/GMT-12	Gilberts, Marshalls, Tuvalu, Wallis & Futuna, Wake
 KP	+3901+12545	Asia/Pyongyang
 KR	+3733+12658	Asia/Seoul
 KZ	+4315+07657	Asia/Almaty	Kazakhstan (most areas)
@@ -220,7 +216,7 @@ MO	+221150+1133230	Asia/Macau
 MQ	+1436-06105	America/Martinique
 MT	+3554+01431	Europe/Malta
 MU	-2010+05730	Indian/Mauritius
-MV,TF	+0410+07330	Etc/GMT-5	Maldives, Kerguelen, St Paul I, Amsterdam I
+MV,TF	+0410+07330	Indian/Maldives	Maldives, Kerguelen, St Paul I, Amsterdam I
 MX	+1924-09909	America/Mexico_City	Central Time
 MX	+2105-08646	America/Cancun	Eastern Standard Time - Quintana Roo
 MX	+2058-08937	America/Merida	Central Time - Campeche, Yucatán
@@ -232,6 +228,7 @@ MX	+2934-10425	America/Ojinaga	Mountain Time US - Chihuahua (US border)
 MX	+2904-11058	America/Hermosillo	Mountain Standard Time - Sonora
 MX	+3232-11701	America/Tijuana	Pacific Time US - Baja California
 MX	+2048-10515	America/Bahia_Banderas	Central Time - Bahía de Banderas
+MY,BN	+0133+11020	Asia/Kuching	Sabah, Sarawak, Brunei
 MZ,BI,BW,CD,MW,RW,ZM,ZW	-2558+03235	Africa/Maputo	Central Africa Time
 NA	-2234+01706	Africa/Windhoek
 NC	-2216+16627	Pacific/Noumea
@@ -245,9 +242,10 @@ NZ,AQ	-3652+17446	Pacific/Auckland	New Zealand time
 NZ	-4357-17633	Pacific/Chatham	Chatham Islands
 PA,CA,KY	+0858-07932	America/Panama	EST - Panama, Cayman, ON (Atikokan), NU (Coral H)
 PE	-1203-07703	America/Lima
-PF	-1732-14934	Etc/GMT+10	Society Islands
+PF	-1732-14934	Pacific/Tahiti	Society Islands
 PF	-0900-13930	Pacific/Marquesas	Marquesas Islands
-PF	-2308-13457	Etc/GMT+9	Gambier Islands
+PF	-2308-13457	Pacific/Gambier	Gambier Islands
+PG,AQ,FM	-0930+14710	Pacific/Port_Moresby	Papua New Guinea (most areas), Chuuk, Yap, Dumont d'Urville
 PG	-0613+15534	Pacific/Bougainville	Bougainville
 PH	+1435+12100	Asia/Manila
 PK	+2452+06703	Asia/Karachi
@@ -260,7 +258,7 @@ PS	+313200+0350542	Asia/Hebron	West Bank
 PT	+3843-00908	Europe/Lisbon	Portugal (mainland)
 PT	+3238-01654	Atlantic/Madeira	Madeira Islands
 PT	+3744-02540	Atlantic/Azores	Azores
-PW	+0720+13429	Etc/GMT-9
+PW	+0720+13429	Pacific/Palau
 PY	-2516-05740	America/Asuncion
 QA,BH	+2517+05132	Asia/Qatar
 RO	+4426+02606	Europe/Bucharest
@@ -293,7 +291,8 @@ RU	+4658+14242	Asia/Sakhalin	MSK+08 - Sakhalin Island
 RU	+6728+15343	Asia/Srednekolymsk	MSK+08 - Sakha (E); North Kuril Is
 RU	+5301+15839	Asia/Kamchatka	MSK+09 - Kamchatka
 RU	+6445+17729	Asia/Anadyr	MSK+09 - Bering Sea
-SB,FM	-0932+16012	Etc/GMT-11	Solomons, Pohnpei
+SA,AQ,KW,YE	+2438+04643	Asia/Riyadh	Arabia, Syowa
+SB,FM	-0932+16012	Pacific/Guadalcanal	Solomons, Pohnpei
 SD	+1536+03232	Africa/Khartoum
 SG,MY	+0117+10351	Asia/Singapore	Singapore, peninsular Malaysia
 SR	+0550-05510	America/Paramaribo
@@ -303,6 +302,7 @@ SV	+1342-08912	America/El_Salvador
 SY	+3330+03618	Asia/Damascus
 TC	+2128-07108	America/Grand_Turk
 TD	+1207+01503	Africa/Ndjamena
+TH,CX,KH,LA,VN	+1345+10031	Asia/Bangkok	Indochina (most areas)
 TJ	+3835+06848	Asia/Dushanbe
 TK	-0922-17114	Pacific/Fakaofo
 TL	-0833+12535	Asia/Dili