Added a Makefile with simple install target.

Makefile

@@ -0,0 +1,21 @@
+PREFIX=/usr
+BINDIR=$(PREFIX)/bin
+RESOURCEDIR=$(PREFIX)/share/gitstats
+RESOURCES=gitstats.css sortable.js *.gif
+BINARIES=gitstats
+
+all: help
+
+help:
+	@echo "Usage:"
+	@echo
+	@echo "make install                   # install to /usr"
+	@echo "make install PREFIX=~     # install to ~"
+	@echo
+
+install:
+	install -d $(BINDIR) $(RESOURCEDIR)
+	install -v $(BINARIES) $(BINDIR)
+	install -v -m 644 $(RESOURCES) $(RESOURCEDIR)
+
+.PHONY: all help install