Run "fragment" on slide change

[nbremer]

A feature request: With the addition of the viewDistance, which is great, I now run into the "issue" that some of my visuals "start their animation" before I get to the page. I'd love it if there was some sort of -1 or 0 (whatever you want to call it) transition state that runs on the slidechange event :) (going forward only I guess)

[gcalmettes]

This feature request is now implemented (634fbfe)!

Adding a transition and giving it a string as index will (e.g.: "start", "onSlideChange", etc ...) will be considered as a slidechange transition (in the forward direction only) and will be triggered when the slide comes into view.

Note that

• (1) there is now a new option for the plugin called onSlideChangedDelay (default: 0) that defines the delay (in ms) with which this specific transition will be triggered after the slide change. See the demo deck for an example of the feature.
• (2) because this transition is not considered an "in slide" transition, it will never be triggered if you go backward (it is disconnected to the fragment system).