Huge shakedown of the testsuite for awesomeness
Huge shakedown of the testsuite for awesomeness

This is too big and messy to easily split over several commits, but the
gist is that tests are now better grouped together, and I've added
linting to satisfy myself that the testsuite is fairly clean and sanely
done.

* Has pylint directives that should give a 10/10 score
* Docstrings up the wazoo on everything
* Some name changes to keep pylint happy
* More consistent input being tested in the send/update functions
* send_{simple,extended} now also tested for write-failure conditions
* Testing for good behaviour if user attempts to write-after-close
* Test that double-closes are handled properly

anchor/pymarquise,anchor/pymarquise