Added scrollbars to the canvas
Scrollbars react when moving viewport
scrollbars work
added "center" button in the corner
Circuit extents includes protoboard. Scrollbars work with zoom.
add crosshair button in the corner
Fixed block increment in horizontal scrollbar
Fixed the unitIncrement. JScrollBar update is invoked later
removed debug information
fixed how circuit extent is calculated
Merge pull request #73 from almejo/VS-50

Add scrollbars for the viewport