Allow for getting the type of an update through a helper method

[PaulSonOfLars]

What

This adds a new Update.GetType() method, which can be used to determine what type of update one is handling without having to check each field. This is autogenerated along with the rest of the lib, so should remain up to date.

Impact

• Are your changes backwards compatible? Y
• Have you included documentation, or updated existing documentation? Y
• Do errors and log messages provide enough context? Y