fixes 9880: use correct grid classes on jumbotron example

BS3 commit c4c87fede5581b848abacc5810afa43b31d6f945
fixes #9879: add hover state to theme buttons

BS3 commit 5bbbdb399bbcd6695fedb73ae9f7b3f6a9300c06
fix 10070 by resyncing fieldset disabled live example & example code. Always wrap form examples in .bs-example; add some missing role='form'

BS3 commits 4912f960f47c8b0008ca6bcfecb629d4a3ee148a,
bc2e97756fcd00747fdc42ee2d58566a70378907
add blog link to homepage

BS3 commit 3318a982290817b40b21a6405b85f791180b5129
docs: add explanation for adding tooltips to disabled elements. tweak 10081 phrasing. repeat 10081 caveat for popovers too. fix data-api portion of 10084

BS3 commits 34db0028757736d924eac6a1b0a25a55b3fbcfcf,
3d7294238427f23a9110f9e00aaa4f7a79222a5f,
0f669b6dcb5c47063c43cd6defcf9697874a0fab,
ec7fa0a25488e2887db9666ea8014777a743ac55