add button to toggle the optional theme when viewing the docs; fixes #9764
regenerate minified docs JS & CSS
Adjust for Scrollspy offset when calculating maxScroll.
Add Scrollspy maxScroll with offset test.
Add tooltip self-reference to address #12320

primarily adds a data- attribute to the tooltip (and thus, the popover)
to create a self-reference.
Adds aria described by to tooltip plugin for accessibility

Generates a unique id for tooltip and adds [aria-describedby] to the element
it is called on. Resolves issue #13480

- set up test
- linted the code styles
- passed the tests
- integrated feedback from @cvrebert
Merge branch 'master' into docs-theme-toggler

Conflicts:
	docs/assets/css/docs.min.css
update explanatory comment about iOS date/time inputs bug

Per:
* http://jsbin.com/purer/2/edit
* https://github.com/cvrebert/bs-css-hacks/blob/6e8aa78384a005b007fc45327c9516dcf6ec0f30/README.md#ios-temporal-input-line-height
Thanks @mdo <3

[skip sauce] [skip validator]
show proper error message when viewing Customizer in IE8

Closes #13090.
[skip sauce]
move it to the sidebar
Reset the padding on radio/checkbox labels in form-inline
Merge branch 'master' into docs-theme-toggler

Conflicts:
	dist/css/bootstrap.css.map
	dist/css/bootstrap.min.css
	docs/assets/css/docs.min.css
	docs/dist/css/bootstrap.css.map
	docs/dist/css/bootstrap.min.css
Merge pull request #13463 from twbs/docs-theme-toggler

add button to toggle the optional theme when viewing the docs
clarify and danger-ify affix docs usage requirements, per #10235
Merge branch 'master' of github.com:twbs/bootstrap
tighten up callouts and remove backgrounds
more callout tweaks
don't change code bg on callouts
grunt dist for docs
clarify