Add version identifier in generated files

Signed-off-by: Lars Hjemli <hjemli@gmail.com>

Makefile

@@ -1,9 +1,10 @@
+CGIT_VERSION = 0.1-pre
 
 INSTALL_BIN = /var/www/htdocs/cgit.cgi
 INSTALL_CSS = /var/www/htdocs/cgit.css
 
 EXTLIBS = ../git/libgit.a ../git/xdiff/lib.a -lz -lcrypto
-OBJECTS = cgit.o config.o html.o cache.o
+OBJECTS = config.o html.o cache.o
 
 CFLAGS += -Wall
 
@@ -13,10 +14,11 @@ install: all
 	install cgit $(INSTALL_BIN)
 	install cgit.css $(INSTALL_CSS)
 
-clean:
-	rm -f cgit *.o
-
-cgit: $(OBJECTS)
-	$(CC) $(CFLAGS) -o cgit $(OBJECTS) $(EXTLIBS)
+cgit: cgit.c cgit.h git.h $(OBJECTS)
+	$(CC) $(CFLAGS) -DCGIT_VERSION='"$(CGIT_VERSION)"' cgit.c -o cgit $(OBJECTS) $(EXTLIBS)
 
 $(OBJECTS): cgit.h git.h
+
+.PHONY: clean
+clean:
+	rm -f cgit *.o