transition for keyword section

altered toggle to have transition. The css3 transition method was even more convoluted because of the transition to an auto height.
I guess it's not really toggleTargetClass if we do all this custom logic... This is kinda  a bummer as the plugin was very generic and is now, yet another very specific, tightly coupled JS widget... I'd love to keep the JS behavioral and keep presentation as a responsibility for the CSS... Maybe there's a clever way we could get the CSS transitions to work.