linux: add patch to add 'Sitecom N300' support

Signed-off-by: Stephan Raue <stephan@openelec.tv>
add TimeoutStopSec=1s (1sec) to some of our systemd services

... to avoid any possible timeouts. those services are fine to be
force stopped by KILL after 1 sec.
remove package: intel-gpu-tools

not needed anymore. implemented in xbmc gotham
update TODO