Expanded bytecode testing code.

def sameMethodAndFieldSignatures compares two classes to verify
they have all the same methods and fields, and no others.
Fix for paramaccessor alias regression.

A binary incompatibility with 2.10.0 revealed a bug I had
introduced in c58647f5f2.
Merge pull request #2100 from paulp/pr/fix-super-varargs-saved

Fixing binary compat for $super regression