added concept of user defined location to anchors. to be used by connection editors.
slight refactoring of flowchart connectors so that the addition of rounded corners is non-destructive on the originally computed set of segments.
extra support on AbstractConnector for the concept of an edited connection
- store min/max of the segments in flowchart connector
- flowchart connector code cleanup a little
added code to clear edits to a connection on paint if requested
temporarily suspend the on click that deletes connections in the flowchart demo
add flowchart connection editor script to flowchart demo
add connector editors script