Updated Java.g4 to work with ANTLR 4.2

Starting in ANTLR 4.2, the assoc option should be placed on the alternative itself.
Merge pull request #70 from diegozaccai/patch-1

Updated Java.g4 to work with ANTLR 4.2
Added missing alternatives in the `UCSCHAR` rule.
Merge pull request #68 from teverett/master

antlr4tester-maven-plugin
Merge pull request #71 from bkiers/patch-1

Added missing alternatives in the `UCSCHAR` rule.