Unhardcode .table-responsive bottom margin
fix .table-responsive media query; refs #11067
remove dupe content
Merge branch 'master' of github.com:twbs/bootstrap

Conflicts:
	getting-started.html
fix about page html validation and run grunt
Merge pull request #11086 from twbs/table-responsive-breakpoint

fix .table-responsive media query; refs #11067
Merge pull request #11084 from ZDroid/variable_way

Unhardcode .table-responsive bottom margin