Use sanitised title instead of plain title.

This avoids failing on titles (ie. image names) with e.g. slashes in them.
Bugfix argument passed to docker run.

Change -volumes-from to --volumes-from.
Refactor to remove big duplicated chunk of code.

Checked for difference between the two blocks first - the only
difference was the apparent typo fixed in ca30f761ace.
Bugfix check of installed tag name.

Don't mistake e.g. installed tag '0.11' for requested tag '0.1'.
Bugfix sanitising of title.

regsubst needs the 'G' argument to replace *all* occurances of
unknown characters, not just the first one.
Merge branch 'bugfixes_upstream' of github.com:SUNET/garethr-docker into SUNET-bugfixes_upstream

Conflicts:
	templates/etc/init/docker-run.conf.erb
Merge branch 'SUNET-bugfixes_upstream'