To ensure that we don't accidentally use any of the aliases.
This should prevent any future regressions from #12761.
Also updates the test suite since it now can't use these aliases either.

[Fixes #15953] Implement `assert.expect` in each unit test

Since only on iOS tests fail when the fixture is displayed off-screen, see https://travis-ci.org/twbs/bootstrap/jobs/52605742

Refs http://qunitjs.com/upgrade-guide-2.x/#replace-qunit-log-callback-with-qunit-log-callback-for-all-reporting-callbacks

Resolves #14919.

...by hiding passing tests in the list of tests.

- Improve comments.
- Remove `transition.js` script load as `transition.js` unit test doesn't exist.

type="text/css" isn't needed

A rebase (against soon-to-be 3.0.0-rc.1) & squash of
https://github.com/twbs/bootstrap/pull/7786 AKA
https://github.com/twitter/bootstrap/pull/7786
originally by
@seriema
@mokkabonna
@jojohess

Rebased by @cvrebert

add preventDefault support for all inital event types (show, close, hide, etc.) + fix small bug with scrollspy.last