KDevelop4 architecture rework

[Alexander Dymo]

Hi!
I've started the rework of the architecture in
branches/work/kdevelop-sublime-integration today.

The goals are (as discussed previously):
- to separate interfaces from shell
- to clean up both shell and interfaces
- to review some design decisions in favor of known working solutions 
  from KDevelop3.

At this point I've refactored Core (made it look and work like KDevAPI
in KDevelop3), PluginController (mostly cleanups) and MainWindow
(it's now Sublime::MainWindow and just waits for more stuff from
Sublime library to be used).

So far the consequences are: clearer initialization procedure, 
minimal interfaces and (still) working plugin architecture.
I'll keep you informed as the rework continues. Feel free to contribute
to this cleanup effort, but just make sure you contacted me at irc before
you start over.
I'd like to refactor Document/Part controllers by myself. Also MainWindow
is my job too. But everything else needs attention as well. For example, the
independent task would be to experiment with inter-plugin deps and BC ideas
(see http://lists.kde.org/?l=kdevelop-devel&m=112620787223741&w=2)
and try to make use of them in KDevelop extension interfaces mechanism.
If everything works ok, project manager needs to be modified so it provides
extension interfaces.

Another task would be to sort out utility stuff that still lies everywhere 
in lib/. Take a look at Matt's reply to "useful stuff in lib" thread for
hints.

Also there're smaller tasks. Removing unused code, checking dependencies
between files and removing extra #include's, reformatting
the code when nesessary.