The macro 'luaL_pushfail' documents all places in the standard libraries
that return nil to signal some kind of failure. It is defined as
'lua_pushnil'. The manual also got a notation (@fail) to document those
returns. The tests were changed to be agnostic regarding whether 'fail'
is 'nil' or 'false'.

A call to 'math.randomseed()' returns the two components of the seed
it set, so that they can be used to set that same seed again.

The previous definition of LUA_MAXUNSIGNED used a typecast,
making it unsuitable for constant expressions in the preprocessor.

- The preprocessor must work with at least 'long', and therefore must
do shifts of up to 31 bits correctly.
- Whenever possible, use unsigned types in shifts.

When called with no arguments, 'math.randomseed' uses time and ASLR
to generate a somewhat random seed. the initial seed when Lua starts
is generated this way.

The call 'math.rand()' converts the higher bits of the internal unsigned
integer random to a float, instead of its lower bits. That ensures that
Lua compiled with different float precisions always generates equal (up
to the available precision) random numbers when given the same seed.

Version numbers and dates (mostly wrong) from RCS keyword strings
removed from all source files; only the file name are kept.

constants

seeds for the PRNG