CHANGED: Cvpcb fpviewer and the pcbnew fpviewer no longer have an options dialog
ADDED: Add a side toolbar to the pcbnew footprint viewer (and the measure tool)
This also cleans up some of the settings structs in the viewers, since
it was somewhat confusing before.
Fixes https://gitlab.com/kicad/code/kicad/issues/2205
Ian McInerney