This change removes a number of wrong usages of the CppModelManager::documents()/document().

Conflicts:
	src/plugins/debugger/gdbtypemacros.ui

More needed. It was suggested to copy parts from the twiki.

Details:  - It will still change if the dependencies change, there's no
way to avoid that though.

when opening files from the C++ editor (e.g. when the user press F2 on #include <QMutex>).

support statements later.

Task:     -
RevBy:    -
AutoTest: -
Details:  -