No logging by default

src/freedombone-app-matrix

     sed -i "s|database: \".*|database: \"${MATRIX_DATA_DIR}/homeserver.db\"|g" "${filepath}"
     sed -i "s|media_store_path:.*|media_store_path: \"${MATRIX_DATA_DIR}/media_store\"|g" "${filepath}"
     sed -i "s|pid_file:.*|pid_file: \"${MATRIX_DATA_DIR}/homeserver.pid\"|g" "${filepath}"
+    sed -i "s|log_file:.*|log_file: \"/dev/null\"|g" "${filepath}"
 }
 
 function matrix_diff {