Some improvements for repository users

run_example.py

@@ -3,6 +3,14 @@
 import sys
 sys.path.insert(0, '../..')
 
+import argparse
+parser = argparse.ArgumentParser()
+parser.add_argument('-p', '--port', type=int, default=5000,
+    help='An alternative port where to run the server.')
+
 from app import app, create_tables
-create_tables()
-app.run()
+
+if __name__ == '__main__':
+    args = argparse.parse_args()
+    create_tables()
+    app.run(port=args.port)