Draggable: Only apply ui-draggable-handle within the draggable instance

Fixes #10212
Closes gh-1284
Draggable: Manage ui-draggable-handle correctly in nested instances
Datepicker: Show year/month on the same line

Fixes #7953
Closes gh-1277
Tabs: Work around bad Safari/VoiceOver heuristics

Move disabled tab click handlers from the container to the tablist to
prevent panel contents from being announced as clickable.

Fixes #10098
Closes gh-1261
Resizable: Remove accidental exposure of internal data in events

Fixes #10148
Closes gh-1279
Dialog: Fix stacking of modal dialog overlays

Fixes #10138
Closes gh-1286
Merge branch 'master' of git://github.com/jquery/jquery-ui into 9264-accordion-heightStyle-auto-has-problems