Rename modules to services.

This is done to simplify the wealth of names Rapid has for things, as well as
to remove any confusion with Ruby's concept of modules.

Anything previously in the Modules namespace is now in ServiceCommon.
Rename ServiceCommon to Services.

Why not?
Rename Server/Launcher to Server/Service.

This should bring it in line with Baps/Service etc.
Standardise Services.

This ensures that:
  * All services inherit from Service;
  * Services refer to the environment as an environment, not a view;
  * Most of the documentation is updated wrt Services.
Merge pull request #45 from UniversityRadioYork/mw-service-module-merger

Merge Services and Modules.