Support mediainfo.

refs #5034

commit 8107852b9934c8e45e93f32fbec832bf3eef7395
Author: Joseph Perry <joseph@artefactual.com>
Date:   Wed May 29 13:21:44 2013 -0700

    Adding mediainfo as a depenency.

    refs #5034
    http://packages.ubuntu.com/precise/mediainfo

commit 7c3d56b4938fc2f34ddc58f07653558902ff7e60
Author: Joseph Perry <joseph@artefactual.com>
Date:   Wed May 29 13:08:51 2013 -0700

    Adding mediainfo to workflow.

    refs # 5034