removed sudo when installing ruby

In the documentation rvm is installed as user miqbuilder which is a local user and rvm gets installed to his profile. So to install ruby there is no need of sudo.
match URL on the current_page instead of the current link

I think this fixes #178, but we'll have to see when it is deployed.
Merge pull request #141 from Ranjandas/patch-1

removed sudo when installing ruby - good to go.
blog post on depot repo
update dev docs
used a global session variable (ugh) to track the rendered page URL

(This works around a bug where page rendering is called within the
search index.)
Merge branch 'master' into depot-WIP

Conflicts:
	config.rb