Revert ""npm link" vanadium instead of "npm install""

This reverts commit d83ac7ed9534e43b99b3930fef52238816842494.
diff --git a/Makefile b/Makefile
index e6aeac7..7fad1ab 100644
--- a/Makefile
+++ b/Makefile
@@ -32,12 +32,9 @@
 node_modules: package.json
 	@npm prune
 	@npm install
-	# Link Vanadium and Syncbase from JIRI_ROOT.
-	@rm -rf ./node_modules/{vanadium,syncbase}
-	@cd "$(JIRI_ROOT)/release/javascript/core" && npm link
-	@npm link vanadium
-	@cd "$(JIRI_ROOT)/release/javascript/syncbase" && make node_modules && npm link
-	@npm link syncbase
+	@ # TODO(rosswang): remove these two
+	@npm install $(JIRI_ROOT)/release/javascript/core/
+	@npm install $(JIRI_ROOT)/release/javascript/syncbase/
 	@touch $@ # if npm does nothing, we don't want to keep trying
 
 server-root: