mention core team maintenance & community contributors

Tested the customizer, the generated zip had:
    css/bootstrap.css:line 6: * Licensed under MIT (<%= _.pluck(pkg.licenses, "url").join(", ") %>)
Revised customizer generates:
    css/bootstrap.css:line 4: * Licensed under MIT (https://github.com/twbs/bootstrap/blob/master/LICENSE)

Carousel: Use the transition duration from CSS

Follow up to reverted commits

Revert commits

Bootstrap is being relicensed from Apache 2.0 to MIT so that more of our community can use the free and open source software we lovely create together. As commits are copyright their original authors, the commits of any individual not agreeing to relicense their contributions are being removed to be later rewritten by the @twbs/team.

This undoes the changes introduced by the following commits:
https://github.com/twbs/bootstrap/commit/7ea34ae0ef79c793e9a9d393b4eef825b71e84b5 , https://github.com/twbs/bootstrap/commit/7376eef378fe7d5e69b8b8cce93c7c64b751d55a , https://github.com/twbs/bootstrap/commit/303ba1326bbe367598ab4cc063b4607507208e56 , https://github.com/twbs/bootstrap/commit/7d1c8c2a0ce16331583a965821690f7715e62908 , https://github.com/twbs/bootstrap/commit/11319f6da9f9a19ec40743cdfe868ac732698149 , https://github.com/twbs/bootstrap/commit/110fc8860117d8675345806219ba313b18086db2 , https://github.com/twbs/bootstrap/commit/ced08f69359f3a70771804a98fa3c499f388cc74

Require comma on left side

enable CSS source maps in grunt-contrib-less

Conflicts:
	Gruntfile.js