Datastore_versions.name shouldn't be unique

The name column in the datastore_versions table is not supposed
to be defined with a unique index. The migrate version 18 was
intended to fix this but the method used to correct the column
definition doesn't work. Added a migrate version 26 to use
UniqueConstraint.drop() instead.

After some discussion, it was decided that downgrade would be
a no-op because it is difficult to reliably create a unique
index on a column with data in it, and further, the column wasn't
supposed to be unique in the first place.

Change-Id: Ida552982de6702db6ed4d40c0167e7d542c0ded4
Closes-Bug: #1310834
Fix prepare call for redis guest agent

Changes:
- The mount point ownership now changed to redis user and group
- Redis restarted to use new config elements

Change-Id: I972cd0c7f6baaed8d8c2a61d096f39a283685237
Closes-Bug: #1298536
Added support of resize-flavor to Redis datastore

trove resize-flavor was not supported for Redis;
If this command is indeed invoked, then the DB VM
would be stuck at the RESIZE state forever, as the
revert function (reset_configuration) is not implemented too;

This patch implements the resizing functionality for Redis

Change-Id: I93a1fe6e583636d72b8d399418d80bd124b36285
Closes-Bug: #1300477
Merge "Datastore_versions.name shouldn't be unique"
Specify correct constraint name for postgresql

The UniqueConstraint is not named 'name,' this causes postgres to fail
with the following error:
UTC ERROR: constraint "name" of relation "datastore_versions" does not
exist
The constraint name should be 'datastore_versions_name_key' in the case
of postgresql.

Since postgres isn't tested in trove's gate yet (Fix:
I53e7fa2729542b88b43cd3de51e15118adaeec57) this has been tested locally
to make sure it stack.sh (which runs trove-manage db_sync) works.

Co-Authored-By: Nikhil Manchanda <SlickNik@gmail.com>
Change-Id: I265925566b8e84d92c838cb3b39ad1f8502cd052
Related-Bug: #1321093
Merge "Fix prepare call for redis guest agent"
Merge "Added support of resize-flavor to Redis datastore"
Datastore version visibility

Change-Id: I7b5bdfcb5dff0a089ebf595b9ad76413662d21d1