zoomDelay, zoomFactor ordering

[quatrano]

Currently, on "mousedown" on a zoom button, there is a zoomDelay, and then the zoomFactor is applied. If the delay is long enough, a quick click can be swallowed, and the zoomFactor will never be applied. Furthermore, this feels like lag to the user.

The zoomFactor should be applied immediately, then the zoomDelay, zoomFactor, ... etc. (The important difference being that the zoomFactor is applied once before the delay.)

Here's the function of interest:
https://github.com/cytoscape/cytoscape.js-panzoom/blob/master/cytoscape.js-panzoom.js#L384

[maxkfranz]

I suppose I'll close this on account of your pull request. Thanks again!