TODO

- Implement trivial examples to test Lexer and Parser, then switch to AST 
generation, and then to full sync with ANTLRv3

- Add implementation of StringTemplate class in PHP 
  (StringTemplateGroup for cminus example)

- Add codegeneration files AST.stg ASTParser.stg ASTTreeParser.stg ST.stg AST.stg ASTTreeParser.stg

- examples: *See TODO in each subfolder.