Send win the message "atom data". win can be 'root-window or an X window identification number. Useful for supporting other WMs module communication protocols. atom is the X11 atom representing the message type (e.g., "XA_WM_PROTOCOLS") and data is up to 4 32-bit integers of data in a list for the message. data will be the used to create the message data, and the lastTimestamp will be appended as the last integer in the data message.