unittests reflect intended API usage

instrumentation/__init__.py

 from satella.instrumentation.insmgr import CounterCollection
 from satella.instrumentation.basecounter import Counter, CounterObject
 
-from satella.instrumentation.exceptions import ObjectExists, ObjectNotExists, NoData
+from satella.instrumentation.exceptions import ObjectExists, ObjectNotExists, \
\ No newline at end of file
+                                               NoData, InstrumentationException
\ No newline at end of file

instrumentation/unittests/callbackcounter.py

 from satella.instrumentation.counters import CallbackCounter
-from satella.instrumentation.exceptions import InstrumentationException, NoData
+from satella.instrumentation import InstrumentationException, NoData
 
 import unittest
 

instrumentation/unittests/countercollection.py

 from satella.instrumentation.counters import NumericValueCounter
-from satella.instrumentation import CounterCollection
-from satella.instrumentation.exceptions import NoData, ObjectExists, ObjectNotExists
+from satella.instrumentation import CounterCollection, NoData, ObjectExists, ObjectNotExists
 
 import unittest
 

instrumentation/unittests/deltacounter.py

-from satella.instrumentation.counters.deltacounter import DeltaCounter
-from satella.instrumentation.exceptions import NoData
+from satella.instrumentation.counters import DeltaCounter
+from satella.instrumentation import NoData
 
 import unittest
 

instrumentation/unittests/numericvaluecounter.py

 from satella.instrumentation.counters import NumericValueCounter
-from satella.instrumentation.exceptions import NoData
+from satella.instrumentation import NoData
 
 import unittest
 

instrumentation/unittests/pulsecounter.py

 from satella.instrumentation.counters import PulseCounter
-from satella.instrumentation.exceptions import NoData
+from satella.instrumentation import NoData
 
 from time import sleep