Add MediaTypeCollection.member_view.

Signed-off-by: Dane Jensen <dane@rightscale.com>
update Gemfile to point to unreleased praxis-bluieprints for now

Signed-off-by: Dane Jensen <dane@rightscale.com>
Merge pull request #51 from careo/media_type_collections-collection_view

Add MediaTypeCollection.member_view.