Fix test cases in integrated.test_multiprocess_api

Fixes bug #1098043

Be patient in test_multiprocess_api while waiting service to be spawned or
killed, because:
    * Service spawning has a limit of one process a second.
    * A test server in the cloud might have limited resources,
      the time there might be several times slower.

Change-Id: If75e6dfa5d769985a6c1b46461f25485e2a996ad
Adding configdrive to xenapi.

This version implements a configdrive v2 for xenapi as discussed
in the xenapi IRC meetings.

 - the config drive is now iso9660
 - the admin password is injected (if we know it)
 - vbd's are not reused
 - review comments have been addressed

Progresses blueprint xenapi-config-drive. DocImpact.

(Dear documentation people, if using config drive with xenapi,
the user should consider disabling the agent as well with
xenapi_disable_agent. This mostly depends on if they want to
support post-boot password updates still.)

Change-Id: Ib23d117ad4cd5dc92298a0812eb468f7d557417c
Correct the calculating of disk size when using lvm disk backend.

Currently, disk space size calculating in nova doesn't consider the
situation when lvm is used as disk backend. Thus both used and total
disk size are not correct when we use lvm to create instance. This
patch fixes this problem by using 'vgs' to get disk size in such case.

Fixes LP #1098116.

Change-Id: I0e86649cfde83a154d0a4c034ca52abe73384e73
Skip domains on libvirt errors in get_vcpu_used()

This commit is to avoid a race condition between deletes
and creates. It is possible for a delete to remove a domain
from the list returned by _conn.listDomainsID() while
get_vcpu_used() is looping over the list. If this happens
libVirt raises a LibVirtError and sets the instance to the
ERROR state. To avoid this LibVirtError is caught and the loop
continues instead of raising the exception.

Change-Id: I3206142e36726936013bb27ccd4359de4f94b3a3
Merge "Fix test cases in integrated.test_multiprocess_api"
Merge "Correct the calculating of disk size when using lvm disk backend."
Merge "Adding configdrive to xenapi."
Merge "Skip domains on libvirt errors in get_vcpu_used()"