self-test.  Because of a change to the way tracebacks are printed,
this self-test was failing.  The test is run (and passes) during normal
regression testing.  So instead of running the failing self-test this
patch makes doctest emit a usage message.  This is better behavior anyway
since passing in arguments is the real reason to run doctest as a command.

Bug discovery and initial patch by Florent Xicluna.

it to do the conversion explicitly instead.  See issue #7550.

Refactored HTTPHandler tests and added testcase for proxy authorization.

math module.

testing on Windows.

instead of a hard coded port number in test_rapid_restart.

any errors that might occur during coercion of the left operand and
turning them into a TypeError with a message text that was confusing in
the given context.  This patch lets any errors through, as was already
done during coercion of the right hand side.

reorganized the distutils doc a bit : the MANIFEST.in template system has its own section now. This is easier to find and follow

sem_unlink calls to delete those semaphore files.

This is for consistency with imitation file objects like StringIO and BytesIO.

This commit also adds a few tests, where they were lacking for concerned
methods.