Added baloo urls into places model

Summary:
Added new sections for places model: 'Recently Saved' and 'Search for' with baloo urls

Based on dolphin code

Depends on D8243

Test Plan:
From an kde app try to open/save a file.
It should show a new file dialog with new categories on the places panel

Reviewers: Frameworks, Dolphin, KDE Applications, dvratil, VDG, ngraham, ervin, mlaurent, dfaure, mwolff

Reviewed By: Dolphin, ngraham, ervin, mlaurent, dfaure, mwolff

Subscribers: mwolff, dfaure, ervin, usta, mlaurent, dvratil, ngraham, Frameworks

Tags: Frameworks

Differential Revision: https://phabricator.kde.org/D8332