Updated openstack/openstack
Project: openstack-dev/devstack  aa29090fe2eeb5ad933b1ad57ed1cb6287a2751c

add LIBS_FROM_GIT to docs

Also reformat common configuration variables to have an additional
header level which makes it easy to direct link to specific
configuration vars when directing someone.

Reformat header markup to us a more standard == = - for h1, h2, h3

Change-Id: I10bac5a93529cdfbcde0a05f9ebdbc1799d403cd