ANTLR v4 Honey Badger early access

Jan 5, 2012

* Deleted code to call specific listeners by mistake. added back.
* Labels allowed in left-recursive rules:
    e returns [int v]
      : a=e '*' b=e {$v = $a.v * $b.v;}
      | a=e '+' b=e {$v = $a.v + $b.v;}
      | INT         {$v = $INT.int;}
      | '(' x=e ')' {$v = $x.v;}
      ;


Jan 4, 2012

* '_' was allowed first in symbol names in grammar
* fix unit tests
* Allow labels in left-recursive rules
* lr rules now gen only 1 rule e->e not e->e_ etc... altered tests to build parse trees.
* no more -trace, use Parser.setTrace(true)
* add context rule option; not hooked up
* 1+2*3 now gives new parse tree: (e (e 1) + (e (e 2) * (e 3)))