Forbidden update message diffs images/tasks/member

On an forbidden update, the message returned to the user
is not tied to the type of object modified by the operation.
For example: a forbidden image member update will return
`You are not permitted to modify 'status' on this image.`
instead of image_member.

This patch fixes the issue for images, image members and tasks.

Change-Id: Ie9774807f0190a517a619aeb56c1398741ac4407
Closes-Bug: #1250228
Remove unused exceptions

Removed the exception classes in the following because not referenced
anywhere.

 -MissingArgumentError
 -NotAuthorized

Change-Id: I9f8d8e865447d772a9c09141b96075620c6d1b07
Closes-Bug: #1259818
Fix and enable gating on H702

Formatting operations should be outside of localization,
otherwise translation lookup will never find a translated
string as a match. This also fixes H701 alongway.

Change-Id: I6708e0f5b11841b18ba9042ac4958643f91396dd
assertEquals is deprecated, use assertEqual instead

Change-Id: Ie67c4c84eb74d7ed27b3c6c253239aaa1aff4862
Cleanly fail when location URI is malformed

At the moment when a malformed URI is passed at either image creation
or update Glance fails with an Error 500. This commit allows Glance
to fails cleanly with a 400 BadStoreUri.

Change-Id: Iffe9be3b65758d18c7e7f96b3ceb3399b9748b63
Closes-bug: #1257498
Merge "assertEquals is deprecated, use assertEqual instead"
Merge "Fix and enable gating on H702"
Merge "Remove unused exceptions"
V2: disallow image format update for active status

The V2 API doesn't not allow empty `container_format` and `disk_format`
when creating a new image.
Currently, it is possible to update these properties after data have
been saved to the image which is contradictory with the previous
statement.
This change disallows modifications of these properties for images with
a status different than `queued`.

Change-Id: I98c22197ba6d96470976718d48ac53748a19ffc6
Closes-Bug: #1249412
Merge "Enable tasks REST API for async worker"
Merge "Forbidden update message diffs images/tasks/member"
Return 204 when image data does not exist

Currently a GET on image-data in glance v2 returns 404 when data does not
exist. But according to the API docs the HTTP status code returned in this
case should be 204.

This fix makes Glance return the right HTTP status code.

Change-Id: I34cf68e96f631f05cff349329245f74aee42397c
Closes-Bug: #1251055
Merge "Cleanly fail when location URI is malformed"
Merge "V2: disallow image format update for active status"
Merge "Return 204 when image data does not exist"
Adds executor interface and example import script

partly implements bp async-glance-workers

Change-Id: I382472fffd0fdad43573e72b2e78a9a6ed1e1f1a
added modification to work on latest rest api

Change-Id: I1fe787194a815b2842044bd6b0e05b4f65014ae7
swift import script

Change-Id: Iabc5b15b5eb27b82fb42e6e600297609237cdc19