KNOWN_EXCEPTIONS don't include all possible exceptions

[raja]

oslo.config may raise a ConfigFileValueError when run server.start(***) in `glance/cmd/api.py`, which is a subclass of ValueError so it can be caught using KNOWN_EXCEPTIONS.

But ConfigFileValueError is not in the KNOWN_EXCEPTIONS, use index method of KNOWN_EXCEPTIONS will raise an ValueError, which is unexpected:

```
2017-10-22 22:47:46.460 94 CRITICAL glance [-] Unhandled error: ValueError: tuple.index(x): x not in tuple
2017-10-22 22:47:46.460 94 ERROR glance Traceback (most recent call last):
2017-10-22 22:47:46.460 94 ERROR glance File "/var/lib/kolla/venv/bin/glance-api", line 10, in <module>
2017-10-22 22:47:46.460 94 ERROR glance sys.exit(main())
2017-10-22 22:47:46.460 94 ERROR glance File "/var/lib/kolla/venv/lib/python2.7/site-packages/glance/cmd/api.py", line 92, in main
2017-10-22 22:47:46.460 94 ERROR glance fail(e)
2017-10-22 22:47:46.460 94 ERROR glance File "/var/lib/kolla/venv/lib/python2.7/site-packages/glance/cmd/api.py", line 65, in fail
2017-10-22 22:47:46.460 94 ERROR glance return_code = KNOWN_EXCEPTIONS.index(type(e)) + 1
2017-10-22 22:47:46.460 94 ERROR glance ValueError: tuple.index(x): x not in tuple
2017-10-22 22:47:46.460 94 ERROR glance

```

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/514114

[OpenStack Infra (hudson-openstack)]

Change abandoned by jiangpch (<email address hidden>) on branch: master
Review: https://review.openstack.org/514114

[Brian Rosmaita (brian-rosmaita)]

Upping the priority as it's impacting interoperable image import configuration. See comments on the duplicate bug.

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/514114
Committed: https://git.openstack.org/cgit/openstack/glance/commit/?id=7edf7ff66dd16d716c7b4935738ccb15f0a83aaf
Submitter: Zuul
Branch: master

commit 7edf7ff66dd16d716c7b4935738ccb15f0a83aaf
Author: jiangpch <email address hidden>
Date: Sun Oct 22 23:17:35 2017 -0400

    Refactor exception handling in cmd.api

    Replace the known exception tuple with a map of exception classes
    to error codes to preserve backward compatibility of exit codes.
    Also change the code to handle unknown members of the Exception
    hierarchy without breaking.

    Co-authored-by: jiangpch <email address hidden>
    Co-authored-by: Brian Rosmaita <email address hidden>

    Closes-Bug: #1726213

    Change-Id: Iabfc2ded45a576a18bdb30a6c3ada8b9799a3196

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/glance 17.0.0.0b2 development milestone.