WIP Add creation of typing context (First pass)

[JSAbrahams]

Relevant issues

resolve #148 fixes #154

Summary

Build a context with all the classes, fields, and functions. This can be used for type-checking purposes when analysing expressions, such as checking that a function called on an expression indeed belongs to that type.

• Remove generics, will be re-added in future

Need to look further into namespaces. At the moment, no import analysis is done either.

Added Tests

• Building context of interfaces
• Building context of classes
• Check that self does not have a type
• Check that all arguments have a type when building context
• Check that if a function has no return type its return type is any (this is not the intended behaviour, so these tests will break once this behaviour has been changed, which we should do eventually)

[JSAbrahams]

Closing in favour of a new architecture.