Handle 'new T()' inside generic methods.
Hack in basic support for recursive generic base classes, i.e. 'Foo<T> where T : Foo<T>':
  TypeRef.get now takes an optional argument 'allowPartiallyConstructed'. If true, it will be possible to resolve a TypeRef pointing to a type that is currently being constructed.
  Fiddled with the order in which type objects are initialized in order to make recursive generic base classes work.