Backfill tests for KVO collections + spies

[Finishes #61156524] tests that KVO collection changes work with spies
rename SimpleCollection to ObjectWithCollection
Move KVO collection spy tests into CDRSpySpec.

Discovered that collection KVO method whitelist was not complete,
added tests to drive out support for spying on KVO observed objects
that contain collections (eg: mutablearray, mutableset, mutable
orderedSet).

Note that dictionaries are not supported by KVO - they
must be wrapped in a custom object that calls the required KVO
boilerplate methods before mutating the dicationary.
Remove focused test
[#61156524] [#149] Add explicit test coverage for properties that are not automatically KVO managed.
[#61156524] [#149] Remove Apple LLVM Compiler 4.0 (and above) array subscript syntax.

- Oops, the subscript call broke on CI due to SDK version, iOS 5.0 env
Merge pull request #149 from boundsj/backfill_kvo_tests

Backfill tests for KVO collections + spies