Misc fixes of tests that were wrong

The just test was basically really outdated and everything is covered
better by the one in descriptortests

Meanwhile descriptortests had a wrong test for equality (you can't
rely on stable printing here)

src/hypothesis/descriptortests.py

@@ -119,7 +119,7 @@ def test_can_round_trip_through_the_database(self, template):
             storage.save(template)
             values = list(storage.fetch())
             assert len(values) == 1
-            assert repr(template) == repr(values[0])
+            assert strat.to_basic(template) == strat.to_basic(values[0])
 
         @descriptor_test
         def test_template_is_hashable(self, template):

tests/test_searchstrategy.py

@@ -100,11 +100,7 @@ def test_int_lists_no_duplicates_in_simplify():
 
 def test_just_works():
     s = strategy(descriptors.just('giving'))
-    assert s.produce_template(
-        BuildContext(random), s.draw_parameter(random)) == 'giving'
-    simplifications = list(s.simplify_such_that('giving', lambda _: True))
-    assert len(simplifications) == 1
-    assert simplifications[0] == 'giving'
+    assert s.example() == "giving"
 
 
 Litter = namedtuple('Litter', ('kitten1', 'kitten2'))