Refactored sheerka class: splitted to use sub handlers. Refactored unit tests to use classes.

tests/TestUsingMemoryBasedSheerka.py

@@ -0,0 +1,10 @@
+from core.sheerka.Sheerka import Sheerka
+from tests.BaseTest import BaseTest
+
+
+class TestUsingMemoryBasedSheerka(BaseTest):
+
+    def get_sheerka(self, skip_builtins_in_db=True):
+        sheerka = Sheerka(skip_builtins_in_db=skip_builtins_in_db)
+        sheerka.initialize("mem://")
+        return sheerka