Better checking, lintable generated code, faster ==

Note that with this change, serializer fields will need to be changed to getters if they are not already getters. The "build" or "watch" script will fail with an appropriate error message if this is the case.

• Enforce that serializer declarations refer to the right generated name.
• Streamline generation for classes with no fields.
• Add identical check to generated operator==.
• Make generated code compatible with strong mode implicit-dynamic:false and implicit-cast:false.