Fixes Issue #16371 Carousel control is vertically off center

[Closes #16460] Fix .pagination-sm line height

[Closes #16447] Manually add license to bootstrap.less

[Closes #16460] Fix .pagination-sm line height by adding `@line-height-small` to `.pagingation-sm`.

[Closes #16447] Concat. license to bootstrap.less

docs examples: input[placeholder]: "Enter email" => "Email"

For uniformity, as we don't seem to use this "Enter <X>" phrasing anywhere else.

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Closes #16372

Improvements to stateful button JS docs

Closes #16362.
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Refs https://github.com/twbs/bootstrap/issues/16362#issuecomment-96268469
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Update JSCS rules

Multiple tooltip triggers don't play well together

Document Affix plugin's `checkPosition` method

Added #panels-footer to components nav in docs

Fix radio and checkbox keyboard handling in .btn-group

Doc that 'manual' is mutex of other tooltip/popover triggers

Closes #16122
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when used with a sticky footer layout.
Adds visual test for affix with sticky footer.

Closes #15694.
Refs #15032.

Fixes #16361
Refs #16356
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Include entire /grunt/ folder in npm package

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Overall logic for this test appears broken, possibly relating to an
older version of Bootstrap that did not require explicit
`data-toggle="button"` on single toggle buttons?

Fix for problem that emerged from #16226 (`.active` class not actually
being applied) and expansion of the script to also correctly handle
keyboard interaction with checkboxes in `data-toggle="button"` groups

Remove role="button"

Downgrade ZeroClipboard for IE8 support