Modify target 'update' to run tests before installation

       * targets.mk: replace 'all' with 'test' in 'update'

targets.mk

@@ -53,7 +53,7 @@ up2:	update
 update:
 	git remote update
 	git pull
-	$(MAKE) all
+	$(MAKE) check
 
 install:	$(INSTSUB)