Tightened syntax of Exception types in catch phrase

Recent changes to the Java Language Specification for Java 7 drew my attention to the catch phrase types. They are allowed to be neither primitives, nor array types, nor have type parameters.

This change is part of an ongoing review of the Java7.g4 grammar in responce to Bug report 7080366 : Grammar bugs in JLS7, http://bugs.sun.com/view_bug.do?bug_id=7080366.