much badge, so wow

Add npm version badge to README

Follow-up to #12857

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removing unnecessary max-width on tables

Use px for font-size fixes #13737

New apple touch icon and favicon

Adds isolated visual tests for javascript plugins (decoupled from docs)....

This way, it works in all browsers.

Conflicts:
	dist/css/bootstrap.css.map
	dist/css/bootstrap.min.css

Fix bug where a panel recieve extra top border when placed within a collapsible panel

Fixes #13478, reverts #10941

Repaint Fixes When Scrolling

set not-allowed cursor on disabled radio+checkbox labels

replace SemVer summary with a link to its website

faster and easier to test/develop js functionality not represented in unit tests, and gives us
a playground for interactions, etc.

It also makes it so developing javascript is now decoupled form jekyll, which should make everything
faster and less painful.

This commit also reverts my filter commit https://github.com/twbs/bootstrap/commit/9900771aa7f1b3ddcee49aec84082104776ace70
which broke scrollspy for dropdowns.

Closes #13702 by merging a rebased version of it.