Task #8887: added convertIntKeysToString and convertStringDigitKeysToInt methods to convert int-based dicts to strings and vice-versa for qpid

Task #8887: one can't mock the 'protected' __call__ method. so renamed it to execute and let __call__ be a wrapper for execte

Task #8758: merge from branch RA-Task8758 to trunk. svn merge did not work, so I used svn diff on branch and svn patch to trunk. For revision history, see branch.

Task #8888: Fix queue options in FromBus and ToBus, and force the use of topics when providing Services (to prevent bugs)

Task #8888: Added open() and close() to RPC class to hide implementation details of __enter__ and __exit__

Task #8888: Service is a frombus listener, so inherit from new class AbstractBusListener -> refactored out duplicate code

Task #8888: added abstract class AbstractBusListener to listen on a bus, and let the user implement one simple handle_message method

Task #8899: Allow broker options to be specified in FromBus/ToBus constructor (final final fix for tests without auto-reconnect, hopefully)