Removed center file production from the code. For Ticket #145.
Merge pull request #147 from STScI-Citizen-Science/remove-center

Removed references to the center drizzled products.
Modified hardcoded test output dictionary to match new conventions. As make_output_dict has not yet been changed, unit tests will fail. For Ticket #143.
Rebasing mast-names off of master, now that master no longer produces center astrodrizzle outputs.