added built-in class mock tolerance for handling description implementation for NS* container classes

For example, if an OCClassMockObject is inside an NSDictionary and some part of the test code calls -[NSDictionary description] (for example, when logging the contents of the dictionary to the console), then these isNS*__ methods are called on its contents.

It's reasonable to expect this to be tolerated since it shouldn't have any effect on test results, and is simply an annoyance to the tester to write extra for stubs for things that aren't relevant to the test.

Change-Id: I2a2d4cf5e9d8beb04c78f1e122bb46443de465ac