GL: Add markers
PlotBackend: change insertMarker parameters
Plot: typo clearMarker->removeMarker
Add Qt cursor change support
Merge remote-tracking branch 'upstream/master'
MPLBackend: typo in signals
GLUT backend: support cursor change
GL backend add marker signals
MPL Backend: Modify markerMoving signals
GL backend: update marker signals
Merge branch 'master' of https://github.com/t20100/pymca
Improves scatter plot support.