Updated description.
Lots of changes in this one:

* Made calls to schedulers dynamic/configurable (addresses issue #19)
* Stubbed out future schedulers
* Parameterized child-spec function (supports issue #12)
* Pass child spec ID to py:start_link (supports issue #12)
* Added functions for dynamically adding more Python servers to the supervisor
  (addresses issue #12)
* Added functions for getting supervisor data (addresses issue #20)
* Fixed issue with hanging process when getting list of supervisor children
  (was caused by calling py:pycall before supervisor finished setting up
  children; fixed by calling directly to ErlPort in py:start_link; addresses
  issue #21)