FLUID-1922: Upgrade to jQuery UI 1.5.3 complete

[Anastasia Cheetham]

I've committed the upgrade to jQuery UI 1.5.3, and resolved  
FLUID-1922. No actual chances to the Fluid code itself were necessary.

I've tested against just about everything, but everyone should please  
update, and keep an eye open for anything strange...

-- 
Anastasia Cheetham                   a.cheetham at utoronto.ca
Software Designer, Fluid Project    http://fluidproject.org
Adaptive Technology Resource Centre / University of Toronto