System tests that are used call get_api_verion and try to get build info failed according to there is no such data

[Tatyanka]

I scope of https://bugs.launchpad.net/fuel/+bug/1515517 developers remove build data in response of /api/version call, so that tests where we rely on this data to check if nailgun api ran fail with
Traceback (most recent call last):
  File "/usr/lib/python2.7/unittest/case.py", line 331, in run
    testMethod()
  File "/usr/lib/python2.7/unittest/case.py", line 1043, in runTest
    self._testFunc()
  File "/home/jenkins/venv-nailgun-tests-2.9/local/lib/python2.7/site-packages/proboscis/case.py", line 296, in testng_method_mistake_capture_func
    compatability.capture_type_error(s_func)
  File "/home/jenkins/venv-nailgun-tests-2.9/local/lib/python2.7/site-packages/proboscis/compatability/exceptions_2_6.py", line 27, in capture_type_error
    func()
  File "/home/jenkins/venv-nailgun-tests-2.9/local/lib/python2.7/site-packages/proboscis/case.py", line 350, in func
    func(test_case.state.get_state())
  File "/home/jenkins/workspace/8.0.system_test.ubuntu.backup_restore_master/fuelweb_test/helpers/decorators.py", line 80, in wrapper
    result = func(*args, **kwargs)
  File "/home/jenkins/workspace/8.0.system_test.ubuntu.backup_restore_master/fuelweb_test/tests/test_backup_restore.py", line 148, in ha_one_controller_backup_restore
    self.fuel_web.restore_check_nailgun_api(remote)
  File "/home/jenkins/workspace/8.0.system_test.ubuntu.backup_restore_master/fuelweb_test/__init__.py", line 57, in wrapped
    result = func(*args, **kwargs)
  File "/home/jenkins/workspace/8.0.system_test.ubuntu.backup_restore_master/fuelweb_test/models/fuel_web_client.py", line 2020, in restore_check_nailgun_api
    build_number = info["build_number"]
KeyError: 'build_number

I believe we can use list nodes call for check if nailgun api is running or not
https://product-ci.infra.mirantis.net/job/8.0.system_test.ubuntu.backup_restore_master/46/testReport/(root)/ha_one_controller_backup_restore/ha_one_controller_backup_restore/

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/249102

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/249102
Committed: https://git.openstack.org/cgit/openstack/fuel-qa/commit/?id=52a184d137e7e284cfb89b9a49798aac12293250
Submitter: Jenkins
Branch: master

commit 52a184d137e7e284cfb89b9a49798aac12293250
Author: vgorin <email address hidden>
Date: Tue Nov 24 12:59:36 2015 +0300

    Change used parameter to check api is runing

    Change-Id: I77bf2a42f89ac29523694f3a6221e5ef8a34b5e1
    Closes-Bug: #1518243