Add lowercase strings to Lua enum reverse table

Step one toward compatibility with case-insensitive legacy command
syntax.
Try to resolve enums old-style if new-style fails

This makes e.g. cmd(blend,add) work like cmd(blend,'BlendMode_Add').
Resolution in this case is case-insensitive like it used to be.
Accept old-style raw values for enum parameters

These will still be checked to ensure they are valid members of the
enumeration, so it's not as ugly or dangerous as it used to be.
Special case player number 1/2 in ApplyGameCommand

This function, oddly, used to take a 1 or 2 for the player number where
other nearby functions (e.g. IsPlayerEnabled) would take the proper enum
value, 0 or 1.  If the old-style syntax (raw number) is used, also use
the old-style interpretation.
Merge pull request #62 from djpohly/enum-compatibility

Backwards-compatible type-safe enum behavior