Update nova_volume_url to cinder_url in CONF files

"Replace nova client with cinder client to use volume" for
bp/implement-volume-extend replaced nova_volume_url with cinder_url.
The purpose of the change was to support Cinder's recently acquired
ability to extend volumes. The original changeset missed the CONF
files, leaving the nova_volume_url artifact.

Change-Id: Ic814d8cef424c4d1e18e531beb9302da9e273eb6
Closes-Bug: #1218152
pep8 checking was added for bin folder

Change-Id: I9b3a8928fb1d0e9c00361e90dcdcd2eb09e8e44b
Closes-Bug: #1218364
Merge "Update nova_volume_url to cinder_url in CONF files"