Read template's expected value orchest test Part-1

In tests under /tempest/api/orchestration/, resources gets
created based on parameters defined in template (yaml, json).
But while verification of output, expected values are hard coded
in tests. Expected values should be read from template only.

This patch adds the helper to load the values from template
(yaml, json) and apply the changes in
tempest/api/orchestration/test_volumes.py

This patch also rename the existing load_template() function
as it read the template and newly added function load the template
This rename the load_template() to read_template in
tempest/api/orchestration/base.py and corresponding calling files.

Partial-Bug: #1327919

Change-Id: Ie0817e20cb7bacdf33b16fb222a7ee9c91109fc8
Fix a few bugs when running with -u

The default conf file locator needed to reference the file another level up.

The config file set/write did not work if more than one option was changed.
I'm not sure why but think it would be better to just read once, set the
options, and write at the end anyway.

If we are updating and a service is there but not mentioned in the conf file,
we change the conf to True so should also add the service to the available
services.

Change-Id: I261f4ba08083cb7ed60c0a5bdd48a4dc16f4c23d
Revert "Add tests for wait_for_server_status"

This unit test class added several race conditions to the unit tests as well as
added a dependency on having a valid tempest config file. At this point instead
of trying to fix all of these issues I'm pushing a revert in the short term and 
long-term we can just fix things and re-push these tests.

This reverts commit ae7c9ac4aac20a2832fe1beeaac0a688c6accbd9.

Change-Id: If6026611f3938be0716ce95491a8ee60a53e8c12
Closes-Bug: #1347096
Merge "Revert "Add tests for wait_for_server_status""
Merge "Read template's expected value orchest test Part-1"
Merge "Fix a few bugs when running with -u"