WP Coding Standards Fixes

I tried to avoid making any kind of structural changes here. The one structure change that I did make is that I moved the Awebber API class into a vendor directory. There are still some issues, but I think this is a good start. The main remaining items are related to data sanitization and escaping, logic of some of the methods, and some other nitpicky items. 

One thing that I left out because it may cause backwards compatibility issues is the fact that your class names Are_Not_Camel_Case. Since the plugin is very early in development and hasn't been downloaded much, I think it would probably be fine to make this change now before it's too late.

I've tested these changes and haven't found any issues, but I recommend that you do your own testing. It's always possible that I screwed something up or some crazy thing snuck in somewhere. :)