Stop unconditionally setting the z-index on sync

This causes a bug where hidden widgets set the z-index of the mask
to their own z-index. The mask z-index is anyway correctly set
previously in _uiSetHostVisibleModal.
Use counter to prevent multiple resume() fires.
Compare form query with getElementsByTagName results rather than count to accomodate injected form(s).
replace areSame => areEqual because older browsers return a string, as opposed to a number
Merge branch 'modal_zindex_reset_by_hidden_widget_fix' into dev-master
build widget-modality
Remove unnecessary <code> tag

Fixes problem on YUIDoc
Build anim. Doc changes only.
Merge branch 'live-docs' into dev-master
Merge branch 'live-docs' of github.com:yui/yui3 into live-docs
Merge branch 'live-docs' into dev-master