This change adds the stub files and fixture data to generate API documentation

for the status updates resource. In doing this, I found that the examples for

this were showing 401 errors rather than the actual data, because of the new

required_features flag. I've added support for this to the API extension in a

couple ways. First, we temporarily enable the feature while doing the requests

to form the examples. Second, the required features are listed in the

documentation output.

Built HTML docs and verified the results.