Bug 989467

This commit does *not* fix the problem described in the Bugzilla.
Rather, when git clone fails when using SSH, suggest using a different
URL scheme so that the authentication is less of a problem.

Here, the SSH URL detection is purely formal.
The passed URL is deemed SSH if one of the following condition is true:
  1. it starts with 'ssh:'
  2. it contains '@' and not '//' (consider http://user:pass@example.com/foo.git)
Bug 989706: Throttler dies if no cgroups are present

https://bugzilla.redhat.com/show_bug.cgi?id=989706

If there were no cgroups present, the `grep` command would fail.
By not expecting a 0 exit status, we can silently ignore this problem.
Small tweaks
Pulled cartridge READMEs into Cartridge Guide
Removed redundant nav section
Consolidated docs for admin/mgmt consoles, cartridges
Add alignment styles to CSS
Link Cartridge Guide to Index
Merge pull request #3206 from nhr/updates

Migrate most origin-server documentation
Merge pull request #3239 from BanzaiMan/dev/hasari/bz989467

Merged by openshift-bot
Merge pull request #3242 from fotioslindiakos/Bug989706

Merged by openshift-bot
Merge pull request #3244 from danmcp/master

Merged by openshift-bot
Automatic commit of package [openshift-origin-cartridge-jbossews] release [0.7.4-1].
Automatic commit of package [rubygem-openshift-origin-msg-broker-mcollective] release [1.12.6-1].
Automatic commit of package [openshift-origin-cartridge-10gen-mms-agent] release [1.26.3-1].
Automatic commit of package [openshift-origin-cartridge-cron] release [1.10.3-1].
Automatic commit of package [rubygem-openshift-origin-node] release [1.12.6-1].
Automatic commit of package [openshift-origin-cartridge-mysql] release [0.6.3-1].
Automatic commit of package [openshift-origin-cartridge-nodejs] release [1.13.4-1].
Automatic commit of package [openshift-origin-cartridge-haproxy] release [0.7.6-1].