Animate edges (now that they're paths instead of lines) #55
Description
#48 converted the edges from svg line elements to path elements, to support rendering text along a path, and also anticipating future requirement to arc the paths in case of multiple edges linking the same pair of nodes ( see #53 ).
But that broke the edge animation which was using gsap svg plugin to animate x1, x2, y1, and y2 positions. So now this needs to be redone.
GSAP's SVGDrawPlugin would be useful, but its a premium feature.
Another option is to use css but that loses the ability to have a dashed line, which is currently used to indicate certain edge kinds.