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'm going to suggest a perhaps simpler way to go here, but feel free to keep things as is - I only suggest this because I tend to find regex a bit difficult to understand.

I think a series of replaces in the right sequence would also work:
flattened_param = param.replace('][','_') # Convert any adjoining brackets to one underscore
flattend_param = flattened_param.replace('[','_') # Convert the opening bracket to an underscore
flattened_param = flattened_param.replace(']','_') # Convert final ending bracket to empty space
You can also chain these replaces together into one line.  I think you'd need the <> handling as well.