wmstartup: Add more services, move service logic out of common.bash

.config/dtfscripts/services/dropbox.dtf

@@ -0,0 +1,13 @@
+#! /usr/bin/env bash
+#
+# Simple wmstartup service
+# Copyright (C) 2018 salt <salt@lap-th-e560-0>
+#
+# Distributed under terms of the MIT license.
+#
+
+source $DTF_SERVICES_DIR/common.bash
+service_name="Dropbox"
+service_process="dropbox"
+service_kill_on_reload="false"
+