Removed copyright from empty files

According to policy change in HACKING:
http://docs.openstack.org/developer/hacking/#openstack-licensing
empty files should no longer contain copyright notices.
Please note, Oslo (nova/openstack/common) not changed!

Closes-bug: #1262424
Change-Id: I26b7d1eabb189f06219b70495d229389b9d3f260
Handle NetworkInUse exception in api layer

In nova-network, if we delete an existing network with port already
associated, a 500 error will be reported and this is not helpful for
end user. This patch catch the network in use exception and raise
an HTTPConflict exception with formatted message.

Change-Id: I7361e461e0eecc0ef6e47fa8ef9a48a24b7d5dfd
Closes-Bug: #1294920
VMware: create utility functions

The following method has been moved to utility functions:
 - _get_values_from_object_properties

This is now in the vm_util module and is called:
 - get_values_from_object_properties

In addtion to this _get_diagnostic_from_object_properties
has been dropped and the code using that method now leverages
get_values_from_object_properties.

This is related to the blueprint vmware-spawn-refactor.

Change-Id: I5033cae8838179b4c1ace327a42dc626493f19e8
Fix state mutation in cells image filter

Stop set pop() operations in the cells ImagePropertiesFilter from
mutating capability state.  This causes a race that can break the
filter between requests.

Closes-Bug #1325705

Change-Id: I901e39046a38ab60c23ddc8762ef5d19a297935b
Don't log TRACE info in notify_about_instance_usage

Exception information was added to notifications a while back and
logging of tracebacks from those exceptions was added as well.  This can
be confusing because the exception information may be suppressed where
it's caught and then unexpectedly logged later.

Change-Id: I040f7c7e5062672356000a1c50c4da2e857a7cbc
Merge "Don't log TRACE info in notify_about_instance_usage"
Merge "Removed copyright from empty files"
Merge "VMware: create utility functions"
Merge "Fix state mutation in cells image filter"
Merge "Handle NetworkInUse exception in api layer"