- change EqualExpression.resolveType() to add additional check
  before reporting an unnecessary cast if one side is parameterized
  and the other is a cast of a base type that may be compatible
  with parameterized type when boxed
- add test to CastTest

Change-Id: I9e3e1be9a0d42965dba9c8dbf629171248d0b26b
Signed-off-by: Jeff Johnston <jjohnstn@redhat.com>