Removes V3 API images and image_metadata extensions

Removes V3 API images and image_metadata extensions as the
same functionality can be accessed directly through glance. Also
removes the associated testcases. There is a discussion about
the decision here:

http://lists.openstack.org/pipermail/openstack-dev/2013-August/012958.html

Fixes the image bookmark links in server information requests
so they point to glance

Partially implements blueprint nova-v3-api

Change-Id: Id32be0c0794b0f4dd220a928345ddf0133e9ffca
Merge "Removes V3 API images and image_metadata extensions"