Changed smalltalk grammar name to start with capital S.
Modified grammar to allow a keyword selector as a base symbol.
Renamed file to match grammar title as this is required in AntlrWorks.
Merged upstream so pull request merges seamlessly.
Added back Smalltalk grammar with capitals so AntlrWorks doesnt show an error.
Merge pull request #32 from jamesladd/master

Filename changed to solve error with Antlrworks. Added Keyword selector as a bare symbol.