Added Medias code and documentation

Added media.less and edited bootstrap.less and responsive.less to manage media components.

Added a section to the documentation (Media, in components.html) outlining how Medias work. Edited bootstrap.css and bootstrap-responsive.css to add the code for the demos

Signed-off-by: Giuliano Velli <wpbrains@giusi.org>
Added Medias code and documentation

Fix for Issue #1711

Added media.less and edited bootstrap.less and responsive.less to
manage media components.

Added a section to the documentation (Media, in components.html) outlining how Medias work. Edited bootstrap.css and bootstrap-responsive.css to add the code for the demos

Signed-off-by: Giuliano Velli <wpbrains@giusi.org>
Merge branch 'media-component' of github.com:wpbrains/bootstrap into media-component

Conflicts:
	docs/components.html

Signed-off-by: Giuliano Velli <wpbrains@giusi.org>
fix jittering of sidenav
add bottom margin back to sidenav for narrow tablets
add affix to zip
Fix bug Collapse broken in IE
Update less/variables.less

https://github.com/twitter/bootstrap/issues/4508

should fix this issue
fixes #4472: manually change mustache file as well for typo
fixes #4473: docs example typo for js affix plugin
fixes #4480: typo in scaffolding page
fixes #4493: typo in dimiss alerts docs
remove entity in content property on dropup carets--not necessary at all
clean up spacing and run make
Merge branch 'UTGuy-master' into 2.1.1-wip
fixes #4517 manually in mustache file as well, typo in docs
fixes #4520: manually fix example html for icon
update version numbers to 2.1.1
add css tests and stuff for #4528
fixes #4530: fix docs nesting cols comments