[events] changing order of triggers so that lostCurrent arrives before becameCurrent

* useful when on the same element (e.g., at init with anim)
* avoid some incoherence
[container-styling] new container-styling extension that propagates data-container-class as a class on the container

* useful to hide the status or to style a slide
* no support in smartsyntax yet though
[includedeck] added support for container-styling extension (+ by default in profile-3)
[container-styling] removed console.log
[smartsyntax] added a way to use the new container-class features, e.g., [*nostatus]
[samples] illustrate new smartsyntax feature
[gitignore] updated .gitignore to not match the new progress extension
[progress] added the progress extension (drop-in replacement of status)
[includedeck] handling of the new "progress" extension (+ using it in place of status in profile-3)
[samples] illustrating the progress extension in the smartsyntax sample
[progress] updated default style
[progress] normalized options -> opts
[progress] force remove padding in css
[progress] advanced evaluation of progress to allow progress bars, fading etc
[samples] illustrating 'progress' new feature in smartsyntax demo (might move that)