assertion of type in tests should be done with assertIsInstance

[Pavlo Shchelokovskyy]

some of heat tests use different variants of assertTrue(isinstance(A, B)) or assertEqual(type(A), B). The correct way is to use assertIsInstance(A, B) provided by testtools.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/61436

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/61436
Committed: https://git.openstack.org/cgit/openstack/heat/commit/?id=10f193ee9221acaba19b22e913c0092ba07e492c
Submitter: Jenkins
Branch: master

commit 10f193ee9221acaba19b22e913c0092ba07e492c
Author: Pavlo Shchelokovskyy <email address hidden>
Date: Sat Jan 4 08:32:19 2014 +0200

    Fix asserttion of types

    Some code in tests is uisng assertTrue(isinstance(A, B))
    or assertEqual(B, type(A)). assertIsInstance must be used instead.

    assertIsInstance is provided by testtools package, so this change is not
    breaking backward compatibility with Python 2.6.

    Closes-Bug: #1259941

    Change-Id: Ib601aebabc0ff0318cd87cc199c808e6b59f7c9f