change dropdown strategy to use an overlay - fixes mobile click anywhere + allows for firefox middle click

Conflicts:
	Makefile
	docs/_site/assets/js/bootstrap-typeahead.js
	docs/assets/js/bootstrap.min.js
	docs/customize.html
	docs/docs.html

#7896: Outline fix

Sets `type="button"` on all buttons in the docs

Removes .tab-focus() on select-fields

Removes outline (especially on select-elements in firefox)

Conflicts:
	docs/assets/css/docs.css

Cleanup form-inline examples in docs

* New padding approach with separate horizontal and vertical padding
variables
* Improved sizing in large and small buttons and form controls
* Dropped the `.btn-mini` (since we have no `.input-mini` to match, and
holy fuck those were small buttons)
* Dropped the `.pagination-mini` as well because once again, to hell
with such small components
* Changed `@line-height-headings` to `@headings-line-height`
* Removed the `@headings-font-family` because it was honestly kind of
useless

Cleaning the navbar docs

* The search form has been deprecated.
* Using pull-* on a list item won't have any effect.

* The navbar is now always 50px high, so no need for that nasty padding
code block anymore.
* The new proposed body padding value also reflects the default navbar's
margin-bottom.
* Fixed the navbar-link example positioning (missing .navbar-text).

Fix glyphicon in "Dropdown in a button group" example

Fix caret position

Fix