Upgrade system, initial implementation of host system upgarder

* created new class for host system upgrades,
  where we create new repo and run puppet
  manifests for host system

blueprint upgrade-to-5-1

Change-Id: Ic1c66a4295642237b93397a45b2b9151f7680a9d
Cluster change type 'interfaces' added

'Deploy Changed' dialog requires 'interfaces' changes for
properly information presentation. Interfaces change has similar
structure to disc change: {node_id=2, name="interfaces"}.

Change-Id: I43ea96e40d38e459c9d0cf68c0c944026b74da81
Closes-Bug: #1291854
Fix flake8 for fuelmenu

Change-Id: I835f8424135e0773dae62436bea4b26739e19ad9
Closes-bug: #1334156
Merge "Upgrade system, initial implementation of host system upgarder"
Merge "Cluster change type 'interfaces' added"
Merge "Fix flake8 for fuelmenu"
Empty Min level logs fix

Closes-Bug:#1328525

Change-Id: Icf6a7ad33a42e9c44b9fc86a69538f57a34f3733
Remove bonds from configuration on node unnassign

- Bonds should be removed from configuration when node
  unnasigned from cluster
- If no admin network group is found, lookup admin interface
  by cidr only on node.nic_interfaces

This bug partially fixed by previous refactoring

Change-Id: Ibafab7d2aa2a3377a6c184a689a2607b4953ee09
Closes-Bug: #1328163
Task helpers partial refactoring added

What is done:
- most methods from TaskHelper class moved to objects.Task;
- code that was dependent on TaskHelper's methods updated
- unit and integration tests updated

What is missed:
- TaskHelper class is still in use as far as it holds several common use
  helper function (in future will be moved to utils module);

Change-Id: Iff2f2a4d277590db25c6f801f20ae75433937411
Implements: blueprint nailgun-task-helpers-refactoring
Merge "Empty Min level logs fix"
Shotgun: make snapshot of entire /var/log

Shootgun uses a fabric.api.get method to download some folder from the
remote host. Unfortunately, this method has a bug and fails when we
trying to download a folder that contains a symlink to another one.

So we need to patch fabric api to prevent us from such falls. The issue
with fabric api is that it recognize all symlinks as a file. As a result
we fails when trying to download a folder (pointed by a symlink)  as
a file.

The patch was proposed to the fabric master branch and can be reviewed
here:

    https://github.com/fabric/fabric/pull/1147

Closes-Bug: #1318514
Closes-Bug: #1323436

Change-Id: Ic2ae889337e5da15bbdf83338b8e8d5d913aeb63
VMware NSX plugin configuration in Web UI

Change-Id: I984105e6b871016ba2b8a2dbb857e76823f019ab
Implements: blueprint neutron-nsx-plugin-integration