Document is_writable.

src/sbbs3/js_socket.c

@@ -1224,6 +1224,7 @@ static char* socket_prop_desc[] = {
 	,"error status for the last socket operation that failed - <small>READ ONLY</small>"
 	,"<i>true</i> if socket is in a connected state - <small>READ ONLY</small>"
 	,"<i>true</i> if socket can accept written data - Setting to false will shutdown the write end of the socket."
+	,"alias for is_writeable"
 	,"<i>true</i> if data is waiting to be read from socket - <small>READ ONLY</small>"
 	,"number of bytes waiting to be read - <small>READ ONLY</small>"
 	,"enable debug logging"