Initial commit.
Demo created according to sources:
http://www.antlr.org/wiki/display/ANTLR3/Five+minute+introduction+to+ANTLR+3
http://www.antlr.org/wiki/display/ANTLR3/Interfacing+AST+with+Java
and
http://www.antlr.org/wiki/display/ANTLR3/Building+ANTLR+Projects+with+Maven
ignore IDEA files + Maven + ANTLR targets
ignore target
Merge branch 'master' of https://github.com/jan-tomsa/antlr-ast2