Add left position for Ff transitions

Firefox's transition support is detected, but not its transform
support; result being that the transition is based on CSS position
rather than translation.

Obviously that needs to be corrected, but my immediate issue is
that because no initial left position is set, there's no transition
when `.next()` is called before manual swiping and consequently no
transitionend event. That's a problem when using pagination like in
the first gallery demo.
Add support for browsers that lack transitions

This effectively adds support for old IE: since it lacks support for
transitions, transitionend events (and consequently the __flip method)
are never fired, breaking pagination and possibly other things.
Merge branch 'ff-friendly'

Preliminary support to produce a working carousel in Firefox,
though not an optimal one. The reliance on vendor prefixes means
Ff's transform support goes undetected and transitions instead
use the CSS left position. Result is predictably janky.