ApiObjectFieldDoc fails on Maps that contain either a key or value that is a ParameterizedType

[jimmorgan]

When resolving a parameterized map in ApiObjectField, the key and value classes are pulled from the parameterizedType actualTypeArguments array and then cast to Class<?>. If the key or value is also a ParameterizedType, then this cast fails. To do this properly, the returned type should be recursively walked until all ParameterizedType returns are resolved. Either that or punt and use the raw type.

Specifically, I have a field declared as:
Map<String, Set> map;
I should expect getFieldObject to either return ["Map", "String", "Set", "map"] or ["Map", "String", "Set", "map"](or, at worse: ["Map", "String", null, "map"])

Handling of generics is probably present elsewhere in the code and might be best handled by a utility method that returns a Class for a given Type.