Fix endpoint usage for glance_http in image client.

Previously the image client was using python-keystoneclient to
generate a new token and to get the endpoint for glance to use
with the glance http library. This was causing permission issues
if the rest client was used to try and delete an image created using
glance_http.

This commit corrects the behavior so that the token and endpoint are
acquired the same way as the rest client so there is no potential
permission issues between the http libraries.

Change-Id: Idff5fcb82019c6b807b87dda480fbcf0b6f8aef2
Update live migration test to use new syntax for create_server

Needed due to change I208b266253c0e48da66d1dd4c84a3c074c38d1a6
which modified the return value and required a new argument

Change-Id: Ic76e375af1ac6bbf2486677706917c8064ff1658
Fixes: bug 1135465
Merge "Fix endpoint usage for glance_http in image client."