Add some documentation on player constants

docs/index.rst

@@ -9,6 +9,7 @@ This is a Python module for implementing bots for Starcraft II.
 
    unit
    managers
+   playerconstants
    
 Short overview
 ==============
@@ -17,10 +18,6 @@ Short overview
    :toctree: _autosummary
 
    library
-   library.PLAYER_SELF
-   library.PLAYER_ENEMY
-   library.PLAYER_NEUTRAL
-   library.PLAYER_ALLY
    library.ABILITY_ID 	
    library.BUFF_ID 	
    library.BaseLocation 	

docs/playerconstants.rst

+Player constants
+================
+
+The following constants are used when referring to a player:
+
+.. autoclass:: library.PLAYER_SELF
+.. autoclass:: library.PLAYER_ENEMY
+.. autoclass:: library.PLAYER_NEUTRAL
+.. autoclass:: library.PLAYER_ALLY
+
+These are internally represented as integers, but these constants should be 
+used instead to avoid confusion.

docs/unit.rst

@@ -38,6 +38,11 @@ Unit
    .. attribute:: Unit.player 
 
       .. TODO: Add page about PLAYER_* constants
+
+      Returns the constant corresponding to player which this unit belongs to.
+      See the page :doc:`playerconstants` for more information on player
+      constants.
+
    .. autoattribute:: position 
    .. autoattribute:: shields 
    .. autoattribute:: tile_position