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. 
Installation and configuration of the Canvas SDK. Bear in mind as well that this URL will change when the SDK moves under Penzance.