Handle mouse events on mouse up.

For some reason the view didn't get mouse-down events (it maybe due to
another Xcode plugin or system wide component).
The mouse-up works fine.
Merge pull request #10 from djromero/master

Handle mouse events on mouse up.
Speed improvements #5 #6
Merge remote-tracking branch 'main-upstream/master'
Updating on theme changes.
Prevent the selection view from jumping around (incomplete)
Better fix for selection view background colour on theme changes
#7 Only cover as much space as needed.
Cleanup
#5 Reverted non contiguous layout because of poor editing performance.
fix GC warning
Merge branch 'master' of github.com:stefanceriu/SCXcodeMiniMap