Add example config

examples/config.py

+SQLALCHEMY_DATABASE_URI = "postgresql+psycopg:///schilder2000"
+# To generate a secret key:
+#   % python -c 'import secrets; print(secrets.token_hex())'
+SECRET_KEY = "abc123"  # Replace me!
+TEMPLATES_AUTO_RELOAD = True
+
+SCHILD_FOOTER = "Organization Without a Cool Acronym – O.W.C.A."
+SCHILD_LOGO = "img/owca.png"