Suggestion for 2 new features: waittoLoad and specify buffer size

[pliablepixels]

Hello, I'd like to suggest the option of 2 new features:

a) Add ability to specify buffer size of rn-carousel-buffered (sometimes 5 is not enough) b) Add ability to specify an auto-slide duration but also specify it should not progress if the current image is not fully loaded - after it gets loaded, then it should move

As far as a) is concerned, I tried changing the 5 here to, say, 10 https://github.com/revolunet/angular-carousel/blob/master/dist/angular-carousel.js#L272 --> while I did see it pre-fetching more slides, it seems to mess up the display of slides after a while