Codestyle corrections

No line should exceed 120 characters.

https://bugzilla.gnome.org/show_bug.cgi?id=728930
Make submodule URL absolute

This makes life easier for people cloning from non-standard (not on
git.gnome) repositories.

https://bugzilla.gnome.org/show_bug.cgi?id=728948
Add empty ovirt

If you now compile, the ovirt-broker.vapi will be distributed among
the other files allowing users to compile it from C level without
ovirt.

Directly compiling from vala sources is also supported through this
changeset.

https://bugzilla.gnome.org/show_bug.cgi?id=725520