add tearDown to a case test

fixes couchforms test:

======================================================================
FAIL: test_basic_edit (couchforms.tests.test_edits.EditFormTest)
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Traceback (most recent call last):
  File "./corehq/ex-submodules/couchforms/tests/test_edits.py", line 49, in test_basic_edit
    self.assertEqual(self.ID, doc.orig_id)
AssertionError: '7H46J37FGH3' != u'6RGAZTETE3Z2QC0PE2DKM88MO'

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clean up two couchform test a bit

to not have the same guid copy/pasted everywhere
WIP
WIP
WIP
WIP
WIP
save cases in test utils
fix case tests
fix couchforms tests
fix receiverwrapper tests

forms are now only saved once!!
fix commtrack tests
move and rename some core couchforms functions
fix an annoying abstraction violation in uth

this also wasn't using locking correctly: it never released the locks
fix phone tests

this is actually likely a live bug as well, and likely what cases
document update conflicts

reprocess_form_cases did not share its caller's case_db
so it was refetching them and saving the cases that were already
in memory; when the caller then went to save those cases it would
error