fixes 10111: different colors for dropdown link hover and active states

BS3 commit 62477653e70270ec386207f5d2d9fcfa0c66fc75
fixes 10164: Document .center-block mixin and update CSS to include it as a class as well. fixes 10115: Default carousel controls and Glyphicon controls should behave the same on small devices and up. fixes 10111: different colors for dropdown link hover and active states

BS3 commits b45c3ea6479e5129f13ab2100b7fffe984c5a935,
d28abc4bf15ab00c7c7587f2fd520218ed6283f1,
62477653e70270ec386207f5d2d9fcfa0c66fc75
Fixed glyphicons count. fixes 10282: Cross reference tabs and tabs plugin

BS3 commits c6d51be2d8ae25f4a78902ca3391b1bc800116ae,
129d8fcebc3e43a7dd03abd2baa8e8134f8e28f3
fixes 10316: Document .active and :active for buttons. fixes 10164: Document .center-block mixin and update CSS to include it as a class as well

BS3 commits 14b3a3542f15051e1274ff27cf9c0cf453b93243,
b45c3ea6479e5129f13ab2100b7fffe984c5a935
alt fix to 10278: Change Google Maps compatibility warning to a general box-sizing warning. fixes 10344: Update IE8-9 support section with table of specific CSS3 and HTML5 features and their support in Bootstrap. fixes 10277: Mention removal of navbar vertical dividers in migration docs

BS3 commits bfda156bb95c115ac9abba880074d4582c81dc0d,
e2c6d329974ac16fab28962fbed089b745a036a5
minor improvements to affix docs. Completion of parentheses. fixes 10282: Cross reference tabs and tabs plugin

BS3 commits f69da1c2ef2717d791fbcdafae78c37b813a6e0c,
93dc003a83c5177149786b5f68699b259de60d2a,
129d8fcebc3e43a7dd03abd2baa8e8134f8e28f3
fixes alignment and nav list in offcanvas example

BS3 commit e8f7d4fcef07a09c2ef767149d7e93a727b3732e
Remove links to navbar examples from example navbars in Theme example--nullifies 9894. fixes 10111: different colors for dropdown link hover and active states. Update index.html (change from 'hero unit' to 'jumbotron')

BS3 commits 8df05b95df85cdd636bcc47c5667c8a198b389df,
62477653e70270ec386207f5d2d9fcfa0c66fc75,
e7f8d0c957babb19f247049d05da0172d94db8f7