Added compatibility with GZDB's new //$Color key.

DECORATE parser now supports both GZDB's $Color key (and its associated
20 hardcoded colors) as well as a new $Colour key (note spelling
difference) which accepts the same kind of strings a wxColour does.
Also fixed an oversight in the tokenizer's new getLine() function so
that it can correctly grab a full line with  special characters in it,
like "RGB(x, y, z)".
Not sure why image conversions stopped working...

But this fixes them. Batch conversions were fine.
Merge branch 'master' of https://github.com/sirjuddington/SLADE
Merge pull request #54 from Gaerzi/master

Sync with my fork.