Use a `method_missing` type tool to allow more readable API calls.

[cycomachead]

The format should be:
Course(1371647).group_categories(50724).groups(queryParams?, cb)
Which is the same as:
Course(1371647).group_categories(50724).groups.get(queryParams?, cb)

But should also exist:
Course(1371647).group_categories(50724).groups.delete(queryParams?, cb)
Course(1371647).group_categories(50724).groups.post(queryParams?, form?, cb)
Course(1371647).group_categories(50724).groups.put(queryParams?, form?, cb)

Where the default arguments format is followed.

[cycomachead]

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Proxy