only emit zoomChanged if the zoom factor changed
optimize ComboBox
- _maximumTextSize seems to be useless (see code marked « IS_MAXIMUMTEXTSIZE_USEFUL »)
- only grow the maximum widget size if necessary (to avoid redrawing almost everything)
emit viewerDisconnected() only if necessary
ViewerGL: fix focus (focus policy was not set), and implement enter/leave event
do not reset _lastRenderedImage when disconnecting + getColorAt now returns a boolean if inside the image
ViewerTab: only disconnect the viewer if it s-was connected
ViewerTab: set the maximum width of the _zoomComboBox, since we know it.
ViewerGL: fitToFormat now works as expected
ViewerGL: fix color picking
Merge branch 'workshop' of https://github.com/MrKepzie/Natron into workshop
update openfx