Allow more ways to disable/enable labels for edges

[nadeem-clearaccept]

As of right now, it seems like I can't disable edge label. As of right now, when hovering over a node, the edge label rendering is causing a performance issue (causing a bit of stuttering on the node hover).

Ideally, I would wish to have the edge labels only show up if a node is selected. I tried to remove the labels and add them back on in the edgeReducer, but it seems like even if there is no label, the performance hit is still there if edge label is enabled.

Ideally, by enabling and disabling the edge label at certain points (when there is less nodes on the screen for example), would improve the performance.

[jacomyal]

Oh, good catch! I haven't displayed edge labels with graphs that are large enough to cause this kind of performance issues yet. I'll investigate this when I can. Thanks for the report!