Switch to side-by-side view

--- a/doc/Makefile
+++ b/doc/Makefile
@@ -6,5 +6,7 @@
 all: upmpdcli.html sc2mpd.html scmulti.html upmpdcli-or-mpdupnp.html \
      releases.html mpdas-upnp.html
 
+upmpdcli.html: upmpdcli.txt upmpdcli-config.txt
+
 clean:
 	rm -f *.html