Added set +e / set -e block around service check.

When running bootstrap-salt.sh on a system that already has salt
installed, but not running, trying to stop salt will cause the script to
exit automatically.
Merge branch 'update_test_docs' into baremetal
Merge branch 'disable_auto_exit_for_service_status' into baremetal
Added test for INSTALL_DEBIAN_INIT_SCRIPT env var.

This will force installing the debian init script.  Useful for
installing in LXC environment.
Merge branch 'add_INSTALL_DEBIAN_INIT_SCRIPT_env_var' into baremetal