Test changes.

One commit makes shutting down the test webserver more reliable, or at least will let errors be reported so that we can  fix them.  We were trapping all exceptions instead of the specific ones we need to catch.  I've narrowed it down to IOError, which is thrown by the request code when it gets a 404 from the server.  Since this is the shutdown sequence, this may be the only exception we care to catch.

The other makes one test case a bit clearer by foregoing a two-element list in favor of simple variable names.  I also reused values that were previously written twice.  This does not change the test functionality.