Improve the function tests

- Execute test groups in serial to make sure no more than 2 database
  instance are created at the same time.
- Remove some unneccesary tests
- Remove unneeded datastore, e.g. 'Test_Datastore_1'
- Remove unsupported trovestack subcommands
- Move unsupported DIB elements to the 'deprecated-elements' folder
- Decrease default value of 'agent_call_high_timeout' to 5min
- Add initial_deplay for pooling task
- Use socket file to connect with database instead of using localhost
  IP

Change-Id: Ie5030a671fbeb453eafa6cbe04e08da7b52e33c9

trove/common/utils.py

@@ -196,7 +196,7 @@ def build_polling_task(retriever, condition=lambda value: value,
             raise loopingcall.LoopingCallDone(retvalue=obj)
 
     call = loopingcall.BackOffLoopingCall(f=poll_and_check)
-    return call.start(initial_delay=False, starting_interval=sleep_time,
+    return call.start(initial_delay=0, starting_interval=sleep_time,
                       max_interval=30, timeout=time_out)
 
 
@@ -209,7 +209,7 @@ def wait_for_task(polling_task):
 
 
 def poll_until(retriever, condition=lambda value: value,
-               sleep_time=1, time_out=0):
+               sleep_time=3, time_out=0):
     """Retrieves object until it passes condition, then returns it.
 
     If time_out_limit is passed in, PollTimeOut will be raised once that