Swipe 2.0: change to start/stop slideshow issues

https://github.com/bradbirdsall/Swipe/issues/180

slide() now stops slideshow like prev and next do.
added stop() and changed begin you can now pause/restart slideshow
added slide duration at an individual item: you can now, in slideshow,
set different durationfor each slide.

itemsDelay Function - overrides the value set in auto at an item value.
You can specifiy the time between slide transitions by item

starts the slideshow (delay: time in milliseconds between slides)