Replace installation script with standard Makefile

Create a standard Makefile that replaces the non-standard installation
script.

Makefile

@@ -0,0 +1,25 @@
+PREFIX ?= /usr/local
+DESTDIR ?= /
+
+man:
+	@txt2tags -o man/xdgmenumaker.1 man/xdgmenumaker.t2t || \
+		echo "WARNING: txt2tags is not installed. The xdgmenumaker manpage will not be created."
+
+install:
+	install -d -m 755 $(DESTDIR)/$(PREFIX)/bin
+	install -d -m 755 $(DESTDIR)/usr/share/desktop-directories
+	install -m 755 src/xdgmenumaker $(DESTDIR)/$(PREFIX)/bin/
+	install -m 644 desktop-directories/* $(DESTDIR)/usr/share/desktop-directories
+	if [ -f man/xdgmenumaker.man ]; then \
+		install -d -m 755 $(DESTDIR)/$(PREFIX)/share/man/man1; \
+		install -m 644 man/xdgmenumaker.1 $(DESTDIR)/$(PREFIX)/share/man/man1/; \
+	fi
+
+clean:
+	rm -f man/xdgmenumaker.1
+
+uninstall:
+	rm -f $(DESTDIR)/$(PREFIX)/bin/xdgmenumaker
+	rm -f $(DESTDIR)/usr/share/desktop-directories/xdgmenumaker*
+
+.PHONY: man clean install

install.sh

@@ -1,24 +0,0 @@
-#!/bin/sh
-
-cd $(dirname $0)
-
-which txt2tags &> /dev/null
-retval=$?
-if [ $retval -eq 0 ]; then
-        cd man
-        txt2tags xdgmenumaker.t2t
-        cd ..
-else
-        echo "WARNING: txt2tags is not installed. The xdgmenumaker manpage will not be created."
-fi
-
-install -d -m 755 $DESTDIR/usr/bin
-install -d -m 755 $DESTDIR/usr/share/desktop-directories
-install -m 755 src/xdgmenumaker $DESTDIR/usr/bin/
-install -m 644 desktop-directories/* $DESTDIR/usr/share/desktop-directories
-
-if [ -f man/xdgmenumaker.man ]; then
-	install -d -m 755 $DESTDIR/usr/share/man/man1
-	install -m 644 man/xdgmenumaker.man $DESTDIR/usr/share/man/man1/xdgmenumaker.1
-fi
-