Feature/base api method

Added a base class for api methods and implemented a READ action in the sections module for getting a list of sections for a course.
So, I looked at both the requests and httplib python libraries and neither defines enums or constants for HTTP verbs, so I'm hesitant to create our own enum class since most pythoners will be accustomed to providing a string value.  Since python doesn't have type enforcement for parameters or return types, any validation (whether class type or string comparison) would have to happen at the point of retrieval much like how the Django CBVs work.   We could have "action" be a class variable and implement a getter that checks if the action is one of GET/PUT/POST/DELETE: I actually had it that way initially, but the fact that it only gives you feedback when you call an associated getter turned me towards the abstractmethod approach.  One other thought that would ensure our generated code is valid would be to have a helper method available for our unit tests that returns a list of the acceptable HTTP verbs and have each of our test classes implement a test that checks the class' verb against that list.