Add nested kbd element styles for actual keys or inputs
text transformation added

Transform text in components with text capitalization classes.
Color Contrast for panel heading

related to #13686
fix variables in panels.less
MD/CommonJS/Globals #12909
Merge pull request #13772 from twbs/fat-amd

AMD/CommonJS/Globals #12909
fix #13220 Scrollspy generates wrong offsets for a page-- recalculate offsets if `scrollheight` changes
button-groups.html: fix grammar: "in on" => "on"
grunt
Merge branch 'master' of github.com:twbs/bootstrap
fixes 13609 - Modal is shifting left just before the hiding animation
hidden and auto
Merge pull request #13785 from twbs/fat-13609

fixes 13609 - Modal is shifting left just before the hiding animation
grunt
fix #13185 - keyboard support for carousel
Fixes #13548: Use position: absolute; to fix checkbox and radio line-height problems that were introduced after #13003
fix thumbnails docs
New text align class, .text-nowrap, for preventing text from breaking to new lines. Applies it to the grid docs table.
fixes #13775: tweak grid nesting docs about # of cols, change up example slightly
homepage copy to fix #13733