- cleaned-up the tests relying on the JVM verifier (with JDK7 fallback to old...

- cleaned-up the tests relying on the JVM verifier (with JDK7 fallback to old verifier is no longer done for classes whose version is 1.7)
- added test to check that there is indeed no fallback to the old verifier (using a class without frames whose version is 1.7)