tools: revamp editor fragments

but them in a single fragment, which is a fragment tab host.
makes all a bit more organized

change layout of the editors too, merge search edit text and turn
the buttons into image buttons.

add some more feedback when saving / applying settings
(for example dialogs and toasts)

add top and bottom shadow just to make it look a tiny bit better.

Change-Id: I3d4e835ab3340b0d40f6d5054590e3952254aafd