G15 on Linux

This version fixes bugs in the API as used by G15Composer. Users of G15Daemon 1.9x and G15Composer are recommended to upgrade to this version of G15Daemon, and G15Composer 3.2.

Changelog includes:
- BugFix: IS_USER_SELECTED client command was broken.
- BugFix: restore client ability to change backlight state.