updated the installer so that it should actually work

examples/os-installer-config-arkdep/scripts/prepare.sh

@@ -0,0 +1,22 @@
+#!/usr/bin/env bash
+
+set -o pipefail
+
+## Generic checks
+#
+# Ensure user is in sudo group
+for group in $(groups); do
+
+	if [[ $group == 'wheel' || $group == 'sudo' ]]; then
+		declare -ri sudo_ok=1
+	fi
+
+done
+
+# If user is not in sudo group notify and exit with error
+if [[ ! -n $sudo_ok ]]; then
+	printf 'The current user is not a member of either the sudo or wheel group, this os-installer configuration requires sudo permissions\n'
+	exit 1
+fi
+
+exit 0