Feature/autogenerate

This pull request add a scripts directory with the generate_sdk_methods.py script and readme included. The script auto generates the SDK methods in the folder canvas_sdk/methods. The auto generated files are also included but should be ignored for the code review. The file to be reviewed is really only the generate_sdk_methods.py. 
I don't think this if statement is necessary if the return from check_for_enums is at least an empty list, but it's probably safe to stay in case it ever returns None.