fixes 13367

BS3 commits: abc797696d9f0b7ad5768092aedcc4620171bfe9
grunt dist

BS3 commits: b2173572527ece62c0e0055ebbc87e986ab1f844
Added bower reference to main less file

BS3 commits: 17f77a5070fa090f351c882750c5cbb3a9c9e0d2
explain

BS3 commits: a80eb1eb50d0c5953c2dc35ceb67ad622aa9a732,
4c3ef52fc12519b59584a4696e6b3eca70551ce8
document grid column wrapping behavior; fixes 13247

BS3 commits: 99f22d97ba4d82faa22c2b3a406dd4058b426e8e