Replace detail for explanation msgs on webob exceptions.

When using detail=msg, a default msg is set and returned.
To let the user know the real cause of the error explanation arg
shall be set with the appropiate error message.

[For example]
$nova --os-compute-api-version 3 service-disable --reason 'A...' host srv
"The server could not comply with the request since it is either malformed
or otherwise incorrect."

By setting the explanation we get:
$nova --os-compute-api-version 3 service-disable --reason 'A...' host srv
ERROR: Disabled reason contains invalid characters or is too long

Change-Id: I380916b110cd021aefcbedd2f943155329860fe7
Fix InstanceNotFound error in _delete_instance_files

Currently the cleanup_running_deleted_instances peroidic task
failed with InstanceNotFound exception, this is because the
db query is not including the deleted instance while
_delete_instance_files() in libvirt driver.

Closes-bug: #1280140

Change-Id: Ie65ff255ad3c582a71db93b07304a21d4976a193
VMware: fix instance lookup against vSphere

Modifies the logic to search the vsphere vm for a given
instance. The change now makes use of the config.extraConfig
property to search for the instance.

Change-Id: Id11f44b9792f196ad627879d082ad829869efcdf
Closes-Bug: #1257038
Clean up _make_*_list in object models to use base.obj_make_list

There are a lot of places where _make_foo_list()s are implemented.
Actually base.obj_make_list() can be used to make the list.

The patch is to clean up the redundancies and make the code clean.

Also, in order to make _from_db_objects()s the same format, we add
'context' into the parameter list in instance fault object.

Related to blueprint icehouse-objects.

Change-Id: I1a68b6e9dc402d4e30a06f94b068233e2afa713f
Remove blank space after print

Check nova code, remove blank space after print.

Change-Id: I0d7f1ebe6e83189a51bf714a2f03afd8a91d515c
libvirt: image property variable already defined

A variable image_meta_prop with properties from a glance image
is already defined and can be used.

Change-Id: I5a3bab2d944c60ed744bbfc79fb9d5ad195c0d69
Merge "Fix InstanceNotFound error in _delete_instance_files"
Merge "Clean up _make_*_list in object models to use base.obj_make_list"
Merge "Remove blank space after print"
Merge "libvirt: image property variable already defined"
Merge "Replace detail for explanation msgs on webob exceptions."
Merge "VMware: fix instance lookup against vSphere"