make services more configurable

[lsmith77]

f.e. the menu service (and/or class) etc.

[nykopol]

Looking at the sources, i think services are already configurable. I think this issue can be close.

[lsmith77]

they are not configurable via app configuration.

[benglass]

I agree that you should be able to specify service ids that could replace the existing services for things like a menu provider rather than having to override the class name parameter which is limited in terms of what you can do (you cant have different constructor arguments)

[dbu]

could be something for version 1.2

[dbu]

removed the milestone. if anybody thinks its important to have it, please create a pull request.

[wouterj]

Removed milestone