moving thumbnail_control.js to the panojs library
fixing IE changes from https://github.com/openmicroscopy/openmicroscopy/pull/1708/files#diff-6cedf73ec464ba34acacbd07b15060eeL124

 - fixing toggleMinimize event as gets handled by too many handlers in FF,
 - fixing ROI to follow mouse cursor when pressed down
Merge pull request #2314 from aleksandra-tarkowska/rebase/dev_5_0/birdeyeview_bug

Birdeyeview bugs (rebased onto dev_5_0)