[filesystem] install/document the filesystem module

MODULES.md

@@ -83,3 +83,10 @@ This binds the keys Meta-F1, Meta-F2 and Meta-F3 to front, back and
 iconify respectively.  The will only have effect inside windows and in
 window frames.  (These are the only places that front/iconfy/back has
 effect anyway.)
+
+## Filesystem module
+
+This is an april fools joke module, but at least it's a starting
+point for building out an icon on the desktop!
+
+Module "Filesystem" "/path/to/open"

Makefile.in

@@ -25,7 +25,7 @@ STRIPFLAG = -s
 PROGS = amiwm requestchoice executecmd ppmtoinfo config_util
 
 MODULES = $(srcdir)/Background $(srcdir)/Keyboard $(srcdir)/Background_resize \
-	 $(srcdir)/Background_stretch $(srcdir)/def_tool.info
+	 $(srcdir)/Background_stretch $(srcdir)/def_tool.info $(srcdir)/Filesystem
 
 OBJS  = main.o screen.o client.o frame.o icc.o \
 		icon.o menu.o diskobject.o gram.o lex.o rc.o \