The basis of this change set is to provide some fixes to certain Tool Shed functions for supporting changing HTTP protocols over time (ie.e, https <-> http).  In doing this, I've refactored several functions and moved most of the Tool Shed <-> Galaxy URL munging functions to the Tool Shed's common_util.py module.  Ive renamed the munging functions to clarify what each of them does.  Several duplicate functions have been eliminated from the code as well.