Filter model working with arbitrary predicates. The exact predicates moved to the data manager view.

Signed-off-by: Rostislav Khlebnikov <r.khlebnikov@gmail.com>
Merge remote-tracking branch 'remotes/origin/bug-18025-Filtering-nodes-in-data-manager-using-QSortFilterProxyModel' into development

Conflicts:
	Modules/QtWidgets/QmitkDataStorageFilterProxyModel.cpp
Merge branch 'development' of https://github.com/rkhlebnikov/MITK into development