Fixes #3811 updating to bootstrap 3

fixes #3510 - plugin interface for registering a plugin, updated menu system

Fixes #2640 - use relative user logout path

Fixes #2502 - session expiration updates

Signo now allows to transparently prolong user session which got
expired. Also when you now logout from Foreman you will end up in Signo
login form. This brings some code clean up and test changes and small
SSO method API change.

new top-bar navigation design and a new login page

fixes #2417 - SSO abstractioning

Apache and Signo SSO reworked to a new general SSO concept.

You can use SSO service that comes with Katello for loggin in. It's
based on OpenID protocol with slightly customized provider.

upgrade foreman to rails 3.2.13

This commit updates from rails 3.0.x to 3.2.x, main changes include:

• Asset pipline support
• cleanup of existing assets (javascript, css, images)

Users who uses foreman in production, make sure that you now compile
your assets, e.g...