in ifdefed out sections

in the right editor from the start

Done based on new IQuickOpenFilter property, isHidden.

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

Task:     Reported on the ML multiple times.
Details:  Add a few methods to make it possible to save and restore
settings. Save those settings to the .ini file. (I'm not sure whether
seesion would be better, let's see what feedback we get.)

Conflicts:
	src/plugins/debugger/gdbtypemacros.ui