Revert "Squashed 'vendor/bootstrap/' content from commit 7f32d15"

This reverts commit ef0ff5b6f0bedbde5ac771a6b18db94d8140bd3e.

This commit doesn't look relevant to the project (accidental?) and
pollutes the project wih files such as LICENSE that don't reflect the
actual license of the project.

Conflicts:
	.gitignore
	less/navbar.less
	less/responsive.less