Re-enable isA and isNotA in the GWT version, and move core logic to a Platform file.  Also test both paths.
Add failure invocations for exception-catching tests.
Add ASSERT.that(foo).has().noneOf(a, 5); to CollectionSubject.
Remove an extraneous comment that was pasted in.
Merge pull request #88 from cgruber/gwtimprovements

Re-enable isA and isNotA in the GWT version
Merge pull request #89 from cgruber/noneof

Add ASSERT.that(foo).has().noneOf(a, 5); to CollectionSubject.