Added tests for signals for struct returning selectors.
Added tests for signals for struct returning protocol selectors.
No structs rather than scalar.
Added selector signal stret assertion.
Extend not supported types.
Merge remote-tracking branch 'origin/signal-for-selector-stret' into selector-signal-docs
Remove unnecessary arguments.
Added more exotic return type methods to RACTestObject.
Rename some methods in RACTestObject for conformity.
Rename methods in the selector signal test protocol so they don't clash with those in RACTestObject.
Changed the tests to expect exceptions.
Added check for struct return types.