Fixed #43 : BnfNodeParser: I can recognize when multiple level of ISA

Fixed #44 : BnfNodeParser: I must simplify results when multiple levels of ISA
Fixed #45 : Dynamic variables cannot be parsed at restart
Fixed #46 : Concepts variables values are transformed into list by default
Fixed #47 : SheerkaAdmin. Add min, max, mean time when restoring files

tests/core/test_SheerkaConceptManager.py

@@ -798,6 +798,34 @@ class TestSheerkaConceptManager(TestUsingMemoryBasedSheerka):
 
         assert sheerka.get_attr(foo, prop) == bar
 
+    def test_i_setting_twice_the_same_property_creates_a_list(self):
+        sheerka, context = self.init_concepts()
+        foo = Concept("foo")
+        prop = Concept("property")
+        bar = Concept("bar")
+        baz = Concept("baz")
+        qux = Concept("qux")
+
+        res = sheerka.set_attr(foo, prop, bar)
+        assert res.status
+        assert sheerka.isinstance(res.body, BuiltinConcepts.SUCCESS)
+        assert sheerka.get_attr(foo, prop) == bar
+
+        res = sheerka.set_attr(foo, prop, bar)  # again, same value as no effect
+        assert res.status
+        assert sheerka.isinstance(res.body, BuiltinConcepts.SUCCESS)
+        assert sheerka.get_attr(foo, prop) == bar
+
+        res = sheerka.set_attr(foo, prop, baz)
+        assert res.status
+        assert sheerka.isinstance(res.body, BuiltinConcepts.SUCCESS)
+        assert sheerka.get_attr(foo, prop) == [bar, baz]
+
+        res = sheerka.set_attr(foo, prop, qux)
+        assert res.status
+        assert sheerka.isinstance(res.body, BuiltinConcepts.SUCCESS)
+        assert sheerka.get_attr(foo, prop) == [bar, baz, qux]
+
     def test_i_cannot_remove_a_concept_which_has_reference(self):
         sheerka, context, one, twenty_one = self.init_test().with_concepts(
             Concept("one"),
@@ -1067,6 +1095,27 @@ class TestSheerkaConceptManager(TestUsingMemoryBasedSheerka):
             'hundred': ['1005', '1007'],
         }
 
+    def test_i_can_resolve_when_concepts_have_multiple_levels_of_sets(self):
+        sheerka, context, adjective, color, red, qualified_table = self.init_concepts(
+            "adjective",
+            "color",
+            "red",
+            Concept("qualified table", definition="adjective 'table'"),
+        )
+
+        sheerka.set_isa(context, color, adjective)
+        sheerka.set_isa(context, red, color)
+
+        by_first_token = compute_concepts_by_first_token(context, [adjective, color, red, qualified_table]).body
+        resolved_ret_val = resolve_concepts_by_first_keyword(context, by_first_token)
+
+        assert resolved_ret_val.status
+        assert resolved_ret_val.body == {
+            'adjective': ['1001'],
+            'color': ['1002'],
+            'red': ['1003', '1004'],
+        }
+
     def test_concepts_are_defined_once(self):
         sheerka = self.get_sheerka()
         context = self.get_context(sheerka)