Switched to forking to better represent server nature of tmux.

- Also added RestartSec option to fix minor issues with restarts trying to
  start the server before it had fully shutdown.

scripts/handle_tmux_automatic_start/systemd_enable.sh

@@ -19,8 +19,7 @@ template() {
 	Documentation=man:tmux(1)
 
 	[Service]
-	Type=oneshot
-	RemainAfterExit=True
+	Type=forking
 	Environment=DISPLAY=:0
 	ExecStart=/usr/bin/tmux ${systemd_tmux_server_start_cmd}
 
@@ -28,6 +27,8 @@ template() {
 	ExecStop=/usr/bin/tmux kill-server
 	KillMode=none
 
+	RestartSec=2
+
 	[Install]
 	WantedBy=default.target
 	EOF