Move glance image service client from nova and cinder.

This is now present in nova and cinder, and it will be also needed in ironic,
so moving it into a common location.

Most of the code was present on nova.image.glance and cinder.image.glance.

glanceclient/exc.py => nova.exception <=> cinder.exception
 GlanceBaseException
 GlanceConnectionFailed
 ImageNotFound
 ImageNotAuthorized
 Invalid

Implements: blueprint image-tools

Change-Id: Ibb2c44df99ae5746e32695e69078737cc6b5aeeb