[System test] Refactor reinstall and partition preservation tests

[Veronica Krayneva]

Create cluster with controller + mongo instead separate nodes for controller and mongo. Because before it was blocked by bug.

Also need delete reinstall_single_mongo_node test and merge mongo_partition_preservation and mysql_partition_preservation tests
and merge cinder_partition_preservation and nova_partition_preservation tests.

Also it can help regression bugs discovering - https://bugs.launchpad.net/fuel/+bug/1475296
https://bugs.launchpad.net/fuel/+bug/1482154

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/222622

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/222622
Committed: https://git.openstack.org/cgit/stackforge/fuel-qa/commit/?id=9e0040fd96eaf709b0da0e8b8fb13463544038ca
Submitter: Jenkins
Branch: master

commit 9e0040fd96eaf709b0da0e8b8fb13463544038ca
Author: Veronica Krayneva <email address hidden>
Date: Fri Sep 11 17:07:07 2015 +0300

    Refactor reinstall and partition preservation tests

    Follow changes were done in this patch:
    - create cluster with controller + mongo instead of
      creating separate nodes for controller and mongo.
    - reinstall_single_mongo_node test was deleted.
    - merge mongo_partition_preservation and
      mysql_partition_preservation tests in
      mongo_mysql_partition_preservation test
    - merge cinder_partition_preservation and
      nova_partition_preservation tests in
      cinder_nova_partition_preservation test.

    Change-Id: I3a6612377ee7cdf7bcc71c0a1d13fba3923896c0
    Closes-Bug:#1494768

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/7.0
Review: https://review.openstack.org/231500

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/231500
Committed: https://git.openstack.org/cgit/stackforge/fuel-qa/commit/?id=af8ee4a5711d1a5de45d6224293ea94bb10bba2b
Submitter: Jenkins
Branch: stable/7.0

commit af8ee4a5711d1a5de45d6224293ea94bb10bba2b
Author: Veronica Krayneva <email address hidden>
Date: Fri Sep 11 17:07:07 2015 +0300

    Refactor reinstall and partition preservation tests

    Follow changes were done in this patch:
    - create cluster with controller + mongo instead of
      creating separate nodes for controller and mongo.
    - reinstall_single_mongo_node test was deleted.
    - merge mongo_partition_preservation and
      mysql_partition_preservation tests in
      mongo_mysql_partition_preservation test
    - merge cinder_partition_preservation and
      nova_partition_preservation tests in
      cinder_nova_partition_preservation test.

    Change-Id: I3a6612377ee7cdf7bcc71c0a1d13fba3923896c0
    Closes-Bug:#1494768
    (cherry picked from commit 9e0040fd96eaf709b0da0e8b8fb13463544038ca)