Example recording an animated camera flight to a high-quality video

Creates videos like http://www.youtube.com/watch?v=-WA3_NShAJk
Fix loading routes with less via points than currently active

REVIEW: 110735
Bring back legend on smallscreen.

BUG: 320475
compile with MSVC
compile successfully if no Phonon is found
factor out ScreenLayer from GeometryLayer
wip idis
GeoGraphicsScene
always create a canvas image in texture mappers
GeoPainter::mapTexture()
const'ify
remove ViewportParams parameter from MarbleGraphicsItem::paintEvent()
const'ify changeViewport()
const'ify GeoGraphicsItem::paint()
split LayerInterface::render() into paint() and setViewport()