[xtext-dev] Removed global service registry

[Sven Efftinge <sven.efftinge@xxxxxxxxx>]

Hi all,

I've removed the service project. So we don't have a service registry  
or service scopes anymore.
- The unit tests run with local state now (they hold a guice injector).
- StandaloneSetup returns an Injector
- [UI] A generated Activator creates and holds injectors
- [UI] Executable Extensions are created using that injector (via  
IExecutableExtensionFactory)

Other changes:
 - Introduced ILocationInFileProvider providing a range for an  
EObject. Default implementation uses the code Peter has written for  
the outline.
 - Added DefaultLabelProvider, so we can inject an ILabelProivder  
(JFace interface).
 - I copied the tests from xtext.tests to generator.tests, so this  
project is as well obsolete.

Cheers,
Sven