Merge pull request #555 from uqam-fob/explorer-os-etc-os-release

explorer/os: get ID from /etc/os-release

cdist/conf/explorer/os

@@ -1,6 +1,7 @@
 #!/bin/sh
 #
 # 2010-2011 Nico Schottelius (nico-cdist at schottelius.org)
+# Copyright 2017, Philippe Gregoire <pg@pgregoire.xyz>
 #
 # This file is part of cdist.
 #
@@ -139,5 +140,12 @@ case "$uname_s" in
    ;;
 esac
 
+if [ -f /etc/os-release ]; then
+   # already lowercase, according to:
+   # https://www.freedesktop.org/software/systemd/man/os-release.html
+   awk -F= '/^ID=/ {print $2;}' /etc/os-release
+   exit 0
+fi
+
 echo "Unknown OS" >&2
 exit 1