Extended hover state of linked versions of .thumbnail

BS3 commits: 036712ed9015c1ea19f2f400526b37c5115446f6
add IDs to frequently-referenced parts of the docs

BS3 commits: 4e1808930a7ad9cbfcf76a5b05ac90bced761eb8
Use bootstrap.less file order in Customizer

BS3 commits: b5d7a51bff673182e2100c6f5b5432127872547d
adding required attribute for example signin form

BS3 commits: a44bd01628d66b92bee3eaef7e4b4f21b5525de6
In docs, recommend only <div> (not <span>) for putting tooltips on disabled elements

BS3 commits: 27e2c56792bcf7df2c0cb9247d373c90cab7c198
run grunt

BS3 commits: b05a287eb6d9cebe8590667ef260dd8ec70d5717
unnest the list-group-item link variation for 11085 and 11088. fix issue with left border of list-group-item

BS3 commits: 710071157751dc9aac1b531d283c1ae756a3c902
unnest the list-group-item link variation for 11085 and 11088. Extended hover state of linked versions of .thumbnail. run grunt

BS3 commits: 710071157751dc9aac1b531d283c1ae756a3c902,
036712ed9015c1ea19f2f400526b37c5115446f6,
b05a287eb6d9cebe8590667ef260dd8ec70d5717
Ditch `&`, as `+ ...` is enought

BS3 commits: 2380b6be9937dfc0ca924a2334adfb21ddb91cc0
Merge branch 'master' into brand