Make unable to ping log messages appropriate level

The ping from an ssh connection checks in _check_remote_connectivity()
aren't necessarily expected to pass on the first attempt. However,
every time the ping was unsuccessful the method would log an
exception which is too severe a log for an expected error. This
commit uses a more appropriate log level for this case.

Change-Id: I8068fa85472259676acebd99b9d191065661e101
Move baremetal API tests to an /admin subdir

To avoid confusion, move all baremetal API tests to api/baremetal/admin and
add a README.rst explaining that the API provided by Ironic is meant to be used
as an admin and service level API.

Change-Id: Ib49b6d5937da6eedc3028a1f831552cf02d9f69e
Router API Tests Enhancements

Add test to creation of router with snat rule
  - Create a router with default attributes
  - Verify the default snat attributes
  - Creating a router using admin priviledges for a tenant
     with snat value True/False
  - Verify routers for snat value True/False by overwriting
     through admin tenant.

Change-Id: Icf2f56f7aa7a2dc736c57daad6d2d5c37e0d9e32
Fix typo in comment

Fixes a typo in flavor response validation.

Change-Id: Ib492e291f5c64a18256cefbda11f81ff33f03861
Merge "Fix typo in comment"
Merge "Move baremetal API tests to an /admin subdir"
Merge "Router API Tests Enhancements"
Merge "Make unable to ping log messages appropriate level"
Merge branch 'master' of https://github.com/openstack/tempest