Return the copy status name when a copy is not available

Return the copy status name when a copy is not available

It looks like the checkout operation used to return a fleshed
config.copy_status object, but that changed and we now get a
raw ccs ID back.

Retrieve the status name using the ccs ID and present that
to the users. Also, in case problems like this happen in
the future, provide a more specific error message and var
name so that it will be (hopefully!) a little clearer what
payload was expected in the first place :)

Resolves https://bugs.launchpad.net/evergreen/+bug/680575

Thanks to Jason Etheridge for a major assist with this bug.

git-svn-id: svn://svn.open-ils.org/ILS/branches/rel_2_0@18898 dcc99617-32d9-48b4-a31d-7c20da2025e4