Adding base services, which serve more or less as interface definitions
Injecting a mail service into the Project Service
webserver.py:
* Centralizing configuration in webserver.py. 

cloud.py:
* Cloud Files Service now adheres to Hosting Service interface. 
* Removing unused get_uri_list method.
* Passing all required configuration stuff to service constructor.

map_email.py:
* Now adheres to Mail Service interface
* Configs passed to constructor
Use a stubbed Hosting Service and Mail Service if running in test mode
Merge branch 'separate_service_impls_from_iface'