set cl-core to py3 by default

bin/cl-core

@@ -1,4 +1,4 @@
-#!/usr/bin/env python2
+#!/usr/bin/env python
 # -*- coding: utf-8 -*-
 
 # Copyright 2012-2016 Mir Calculate. http://www.calculate-linux.org

bin/cl-core_py2

@@ -0,0 +1,21 @@
+#!/usr/bin/env python2
+# -*- coding: utf-8 -*-
+
+# Copyright 2012-2016 Mir Calculate. http://www.calculate-linux.org
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+
+import calculate.core.core_main as core_main
+
+if __name__ == '__main__':
+    core_main.core_main()