note: this will likely break things for people in the same way that doing
this to tooltip did… however we think this is a better insertion model for
z-index,scrolling,modal,etc. applications

* Fix as documented here: https://github.com/twitter/bootstrap/issues/4756#issuecomment-9952781
* Stops propagation for touchstart for dropdowns

Fix for Bootstrap issue #6013 "scrollSpy - offset calculation"
https://github.com/twitter/bootstrap/issues/6013

Fix test to catch issue.
Fix #5806.

Avoid loosing events attached on Jquery object if added via function in popover content

Fix for issue [5362](https://github.com/twitter/bootstrap/issues/5362):
tab events fired on wrong dropdown anchor.

Also fixes dropdowns hiding behavior for case when two or more dropdowns
with [data-toggle=dropdown] exist on the page

remove modal-open class
hopefully resolve z-index headaches

only stop prop on form – as people seem to be relying on dropdown hiding when clicking internal elements