Description of problem:

In Ussuri release we have added new functionality to import image in multiple stores or copy existing image in multiple stores. To ease user experience we have given a option --all-stores in glanceclient which avoids user to specify all the configured stores explicitly for these new operations.

Now, if operator has configured read-only 'http' store and while creating or copying image if user has specified --all-stores true then depending on `allow-failure`; if it is True then image is imported/copied to other stores than http or if it is false then image can not be imported/copied to other stores as well. Also, new image property `os_glance_failed_imports` shows `http` as failed store.

Expected result:
If operator configures 'http' store as then it should not be included in import/copying operation if --all-stores specified by user.