Implement Implicit Type Parameter processing

[stephen-zhao]

Implicit type parameters are needed for operators that cannot infer the types of their parameters, so need general types. The following functionality is needed for this:

1. Object::inferThatType (on a formal parameter) upon returning None will make the decision to prepend the current formal parameter with a type parameter
2. Unique type parameter name generation
3. In an ApplyExpr a type parameter has to be automatically/implicitly passed in before the actual parameter