Why if cell goes off screen, and oscplayer is restarted do connections still drawn off screen?
Theory: The connection holds a ref to the cell, so when the cell gets deleted from the master cell_dict it is still
ref’d in the conx. Therefore, when we iterate through the conxs, they are still taking their location from the former
cell.  The conx on the other hand is prob just put on the suspect list rather than deleted.
Solution: Delete the conx along with the cell
5/27/2014
* Diagnosed a prob where the connectors of deleted cells were being drawn to
    their former locations
* Readded pathgrid routines
* Rejiggered path scaling routines based on new scheme
* Added exception handling for keyboard interupt
* To visual sys, added capability to draw pathgrid (press SPACE)