vhpidirect(arrays/matrices/framebuffer): future work

[umarcor]

vhpidirect/arrays/matrices/framebuffer was merged in #20. These are ideas to enhance it:

• X11 backend:
  • Allow using a canvas smaller than the screen/pixmap.
  • Allow resizing the canvas without loosing the screen/pixmap.
  • Exit cleanly when the window is closed.
  • Detect specific keys to provide feedback to the simulation?
• Install imagemagic in the Windows CI jobs.
• Test the X11 backend in (GNU/Linux) CI jobs through xvfb. Record it to a video/gif and upload it as an artifact.
• Add further backends to change the transport layer and use a system framebuffer device (as done by Yann and Martin).
  • Extend it to a remote pipe, i.e., to run the simulation on a device without monitor and have the virtual screen drawn in a different workstation/laptop.
• Pass a fat pointer to save_screenshot, in order to avoid passing width and height explicitly.