Update scrollspy.js

Scrollspy target in tab content does not work properly. Calling .parents('.active') will return all parents with an active class (including the tab pane). Changing this line to .parentsUntil(this.options.target, '.active') should resolve the issue. This will scope the query to only search for active elements inside the scrollspy target.
Added unit test for removing only active class from within the scroll spy key.
Fix: IE10 or lower incorrectly determines the scrollheight of the body. Use document.documentElement for IE. To make this browser agnostic, the maximum scrollheight of both body and documentElement is used.
Fix: IE10 or lower incorrectly determines the scrollheight of the body. Use document.documentElement for IE. To make this browser agnostic, the maximum scrollheight of both body and documentElement is used.
Fixed flickering and simplified calculations

- Removed offending line causing a flicker to the default top state
- Simplified calculation of the top offset when in the bottom state
Fixed typo at docs/examples/rtl/index.php

The filename generated at dist/css/ called 'bootstrap-rtl.min.css'.
Merge pull request #13018 from ORiON-/master

Fixed typo at docs/examples/rtl/index.php
Run usebanner before cssmin.
Simplify tasks a little bit.
Merge pull request #13012 from twbs/banner
add role="alert" to Alert examples, to improve accessibility

Per https://github.com/paypal/bootstrap-accessibility-plugin/blob/d8fcbcd3fe86f0cb47fda0ffe269b2c7a2131f07/README.md#alert
rework docs copy: inputs-without-labels are likely the more common case
Gruntfile.js: fix path after d08bbdc6ec50baca9e34d2aa6e8bcfc8d6135217.
Merge pull request #13024 from twbs/role-alert

add role="alert" to Alert examples, to improve accessibility
comply with .dropdown-menu.pull-right deprecation in docs
Update dependencies.
use stricter error checking in uncached-npm-install.sh

Closes #13045
Merge pull request #13039 from twbs/dropdown-pull-right-deprec

comply with .dropdown-menu.pull-right deprecation in docs
remove unnecessary direct devDependency on css-flip
upgrade to grunt-css-flip v0.2.0