Use nesting for thumbnail styles

BS3 commits: b6a083e77fac4979cf901893fef7bd36fce19fd8
Don't explicitly reference global jQuery. re-grunt

BS3 commits: f1b0cd491c4e3a0a564d92e145c1ecf55105557f,
89d489dfc701273b1898b69bde04cf5eb58b9f85
Add a branch alias

BS3 commits: 375b9edb419a0615bb70b399eea0b81f2f0ef48f
Add toogle nav for screen readers in examples. fix 1 remaining instance

BS3 commits: a063e1f736fb4255f4445dba0be18f08bfab8687,
d2e710a2dfb1a6b4eaccedd975b96b24baa12390