removed Whonix's grml-debootstrap fork, because Whonix's patches were merged upstream
got rid of /usr/lib/whonix/whonix_repo_r_config_exists; refactoring
whonix_shared/usr/lib/whonix/process_killer_helper -> whonix_shared/usr/lib/whonixcheck/process_killer_helper
Merge remote-tracking branch 'origin/master'