Improve hostname setting (#534)
Improve hostname setting (#534)

* - hostname setting
  + Consider different locations for executables on different distributions
  + Prefer hostnamectl when available
  + Verify rsyslog service exists before attempting to restart
  + Do not depend on distro behavior that allows restart of service without
    the .service extension

* Add a period to the end of a comment.

illfelder/compute-image-packages,wrigri/compute-image-packages,zmarano/compute-image-packages,zmarano/compute-image-packages,wrigri/compute-image-packages,rjschwei/compute-image-packages,illfelder/compute-image-packages,GoogleCloudPlatform/compute-image-packages,wrigri/compute-image-packages,rjschwei/compute-image-packages,wrigri/compute-image-packages