Add PEP 8 compliant api, and add deprecation warnings to camel case api methods.

[AndKaminer]

The camel case python API does not follow PEP 8, and I found it a little tricky to tell between scala and python methods. To fix this, I added new, duplicate methods, that follow (in my opinion) pythonic naming convention. Some of the duplicate methods can be seen below:

I also added a deprecated_api_warning method to utils.py.

I then stuck it in to every camel case method.

Potential follow ups:

• Remove any actual functionality from the camel case API and have them just be wrapper functions for the snake case methods that throw up a warning when used.
• Implement more elegant warning logging
• Something else?

Any feedback would be greatly appreciated!