Add demo and scripts to python manifest

MANIFEST.in

+include synctl
+include LICENSE
+include VERSION
+include *.rst
+
+recursive-include synapse/storage/schema *.sql
+
+recursive-include demo *.dh
+recursive-include demo *.py
+recursive-include demo *.sh
 recursive-include docs *
+recursive-include scripts *
 recursive-include tests *.py
-recursive-include synapse/storage/schema *.sql
-recursive-include syweb/webclient *