Added dummy Makefile.am in doc.

Added Makefile.am in doc/man which supports multilanguage man pages
install/uninstall.

If there is a new man page language available create a subdir named after the lang and append it's name to MAN_LANG here.

doc/Makefile.am

@@ -0,0 +1 @@
+SUBDIRS = man

doc/man/Makefile.am

@@ -0,0 +1,22 @@
+MAN_LANG = de
+dist_man6_MANS = wesnoth.6 wesnothd.6 wesnoth_editor.6
+
+install-data-hook:
+	for i in $(MAN_LANG); do \
+		mkdir -p $(mandir)/$$i/man6 ; \
+		for j in $(dist_man6_MANS); do \
+			$(INSTALL) -c -m 644 $$i/$$j $(mandir)/$$i/man6/$$j ; \
+		done \
+	done
+
+uninstall-hook:
+	for i in $(MAN_LANG); do \
+		for j in $(dist_man6_MANS); do \
+			rm -f $(mandir)/$$i/man6/$$j ; \
+		done ; \
+		if test -d $(mandir)/$$i/man6 ; then echo `rmdir $(mandir)/$$i/man6` ; fi ; \
+		if test -d $(mandir)/$$i ; then echo `rmdir $(mandir)/$$i` ; fi ; \
+	done
+	if test -d $(mandir)/man6 ; then echo `rmdir $(mandir)/man6` ; fi
+	if test -d $(mandir) ; then echo `rmdir $(mandir)` ; fi
+