replace redshift with gammastep for wayland compatibility

gammastep/hook.sh

@@ -0,0 +1,19 @@
+#!/bin/sh
+
+notify(){
+	notify-send \
+		--app-name=redshift \
+		--urgency=low \
+		--icon=redshift \
+		--hint=int:transient:1 \
+		"${1}" "${2}"
+}
+
+case $1 in
+	period-changed)
+		notify "Gammastep" "Period changed to $3"
+		;;
+	*)
+		notify "Gammastep" "Gammastep just fired an unknown hook with these options: '$*'. Ah, of course, this notification is just here, to troll you! :-P"
+		;;
+esac