ARC compliance and some fixes

Removed all calls to [self init...] as they might cause undefined behavior under ARC.
Improved the class family testing for selectors that need to call retain.
Fixed a block not being copied problem.
Fixed a should receive expectation with Class arguments not passing the verification.

References:
http://clang.llvm.org/docs/AutomaticReferenceCounting.html#semantics-of-init
http://clang.llvm.org/docs/AutomaticReferenceCounting.html#method-families