Example shows very old permission handling

[cconard96]

As seen at least here: https://github.com/pluginsGLPI/example/blob/9e17e9d8fa5b56945f058b1cf599ccf8454bfdee/setup.php#L88

The plugin shows storing permissions in individual Session properties using characters to denote the permission level like r (read), w (write), etc. As far as I can tell, GLPI hasn't handled permissions like that in over 10 years.

Discussed here: https://forum.glpi-project.org/viewtopic.php?pid=509952#p509952