Fix some typos in architecture doc

As a new person on this project, I found this document to be excellent.
Fixed a few typos found while reading:
Change where we refer to Havana in the future tense.
Capitalize Ceilometer when referring to the project.
Other small typos

Change-Id: I2fc422950538135fbcf38c468401b4a5cf8640f2
Fix measurement docs to correctly represent Existance meters

There are various meters in the measurement docs that
wrongly note the meter as Duration instead of its
existance. The meters fixed include network, port,
router, subnet, floating ip, volume.

fixes bug #1252988

Change-Id: I45a84769d6ee46d53e580ae08cbbf32ed20562b1
Fix docs on what an instance meter represents

instance meter is a gauge which meters an instance
itself. The current description of duration of
instance is misleading.

fixes bug #1266313

Change-Id: I902606928fc59f5663d638d05f237fe3e5e1175d
Correct a misuse of RestController in the Event API

When nested RestControllers exist, in order to determine which
arguments are associated with the parent resource, pecan looks at the
get_one() method signature in the parent controller.

TraitsController needs the EventTypesController.get_one method to exist in
order to properly pass the `event_type` identifier.

Change-Id: Ic1704c8f9c810ada4e22e8de75ef2511006e8d9d
Merge "Fix docs on what an instance meter represents"
Merge "Fix measurement docs to correctly represent Existance meters"
Merge "Fix some typos in architecture doc"
Update oslo

This updates to:

commit b3e5166e3f47148856d898c4653b0c089c2315f5
Merge: 0002ffa 39e1c5c
Author: Jenkins <jenkins@review.openstack.org>
Date:   Thu Jan 30 10:18:54 2014 +0000

    Merge "Move db tests base.py to common code"

Change-Id: Iaa76b1165e195f0c3874bc5c8bcbc9ecbb6ca5d7
Merge "Correct a misuse of RestController in the Event API"