Updated to Angular 1.2.3.
Added a file for debug utilities.
Added assertions, fixed an error message.
Fixed a very wierd problem.
Having a nested <g> element for connections (under the <g> with the ng-repeat) was causing all subsequent svg elements to be wiped out when there are no connections to display, which breaks rendering of the dragging connection which appears
later in the svg.  I'm not sure why this was a problem but after some experimentation I discovered that collapsing the nested <g> into its parent fixes the problem.
This was only a problem with svg, I tried to replicate the problem with HTML elements to no avail.
It also didn't seem to be a problem with the template itself, I was able to move all the svg inline into index.html and the problem still happened.