More vertex pushing

[samreid]

From #125

In general, this seems to be working, but in reviewing #113, I ran into this situation.

The battery and resistor on the right side of the black box look like they may have potentially overlapped, so the resistor rotated. However, the the components didn't actually connect.

and

@phet-steele found another interesting case:

After the vertex is cut, the central vertices are likely close enough to trigger the rotating behavior, but the wires don't seem to "realize" they are too close until another component is brought close.

The few issues I've observed seem to be edge cases, rather than blocking issues. I'm going to reassign to @samreid, as I'm not sure how he'll want to proceed.

[samreid]

Oops, duplicate, closing.