Add nested kbd element styles for actual keys or inputs
Changed last-child to first-child
As noted by @jerem the first child will actually be the last shown
replace js scrollspy test for default behavior
add button to toggle the optional theme when viewing the docs; fixes #9764
regenerate minified docs JS & CSS
Fixes #13478, reverts #10941
Revert "Temporarily revert README deletions from #13470,"

This reverts commit 54284a13c6b503d925bf6f75db2830f1af7fcf98.
Merge branch 'master' into icon_paths

Conflicts:
	dist/css/bootstrap-rtl.css
	dist/css/bootstrap.css.map
	dist/js/bootstrap.min.js
	docs/dist/css/bootstrap.css.map
	docs/dist/js/bootstrap.min.js
Merge branch 'master' into icon_paths

Conflicts:
	dist/css/bootstrap.css.map
	docs/dist/css/bootstrap.css.map
Customizer: Alert on successful save to Gist
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.
change note in .resizable() mixin for accuracy

Not a Safari bug. It's standards-compliant.

Quoting from http://www.w3.org/TR/css3-ui/#resize :
> ### 8.1. `resize` property
>
> * Applies to: elements with `overflow` other than `visible`
>
> The `resize` property applies to elements whose computed `overflow` value is something other than `visible`.

Original comment was added in commit 648c4689273647c321dd6e3979d910282e9a9339.
more precise docs link
reference other more recent source regarding the IE viewport bug
docs: sort tooltip & container options for sanity
add 'viewport' option to popover docs; #12328 erratum
add multiple triggers info to popover docs
add 'selector' option motivation to tooltip docs