Add templating callback 'beforeAdd'; add callback arg 'isFirstExecution'
Don't call jQuery.cleanData when beforeRemove callback is supplied
Improve jQuery specs
Fix tests
Merge branch 'beforeAdd' of https://github.com/aknuds1/knockout
Merge branch 'jquerydata' of https://github.com/aknuds1/knockout

Conflicts:
	spec/defaultBindings/foreachBehaviors.js
Revert to old caption check, but add allowance for blank caption
Merge branch 'pull-request/caption' into hotfix/caption
Merge branch 'hotfix/caption'