Clear new or building backups on reset-task-status

The reset-task-status management call now also clears off
any new or building backups for the instance by marking
those backups as FAILED.

Fixes Bug # 1205471

Change-Id: I478782b5e90c9965b91169a784b2ea65bda8a8b4
Adding volume size to the backup views/models.

* Save the size of the guest before running a backup
* Display the size in the backup GET/LIST views
* Simplify the dbaas module removing redundant class.
* Switch get_filesystem_volume_stats to use os.statvfs()
* Change output of volume stats to return used in GB
  to simplify various view that display it.

Implements: Blueprint backup-volume-size

Change-Id: I860427d3491acb34e43ee23f91e4ffbb39e0042c
Fix spelling of python.

Change-Id: I717ca931854f32b79c13a81fd635327c52624c63
Replace nova client with cinder client to use volume

Now cinder support a few new features like extend volume which used in Trove.
We can't use nova client to enjoy this new feature, so we should change to use
cinder client as volume management.

implement bp implement-volume-extend

Change-Id: I4f9139bacd7d8b4c2538bff6aa54416b27c9026e
Merge "Replace nova client with cinder client to use volume"
Merge "Fix spelling of python."
Merge "Clear new or building backups on reset-task-status"
Merge "Adding volume size to the backup views/models."
replication initial

moved clustertype to trove directory

removed dummy cluster api

mocking up against the flavors api instead

refactor to use real a more OO approach

adding unittest coverage

added proboscis

remove proboscis

setup maps
fix update to insert
fixed up unittests