Added a "How it Works" section to docs.

This sections walks through many details of how natsort works,
with examples. These examples are tested with doctest, but
only on Python 3.

1 files changed, 13 insertions, 5 deletions

diff --git a/tox.ini b/tox.ini
index ae34b3c..9f56b56 100644
--- a/tox.ini
+++ b/tox.ini
@@ -10,7 +10,7 @@ envlist =
 [testenv]
 commands =
     {envpython} -m pytest --doctest-modules natsort
-    {envpython} -m pytest README.rst docs/source/intro.rst docs/source/examples.rst
+    {envpython} -m pytest README.rst docs/source/intro.rst docs/source/examples.rst docs/source/howitworks.rst
     {envpython} -m pytest
 deps =
     pytest
@@ -26,6 +26,10 @@ deps =
     argparse
 
 [testenv:py27]
+commands =
+    {envpython} -m pytest --doctest-modules natsort
+    {envpython} -m pytest README.rst docs/source/intro.rst docs/source/examples.rst
+    {envpython} -m pytest
 deps =
     pytest
     pytest-cache
@@ -34,18 +38,22 @@ deps =
     mock
     pathlib
 
-[testenv:py33]
+[testenv:pypy]
+commands =
+    {envpython} -m pytest --doctest-modules natsort
+    {envpython} -m pytest README.rst docs/source/intro.rst docs/source/examples.rst
+    {envpython} -m pytest
 deps =
     pytest
     pytest-cache
-    pytest-faulthandler
     hypothesis
+    mock
     pathlib
 
-[testenv:pypy]
+[testenv:py33]
 deps =
     pytest
     pytest-cache
+    pytest-faulthandler
     hypothesis
-    mock
     pathlib