Build: use lerna 2.x beta (#3509)

lerna changelog

update

Makefile

@@ -52,15 +52,14 @@ publish:
 	rm -rf packages/*/lib
 	BABEL_ENV=production make build-dist
 	make test
-	./node_modules/.bin/lerna publish
+	./node_modules/.bin/lerna publish --only-explicit-updates
 	make clean
 	#./scripts/build-website.sh
 
 bootstrap:
 	npm install
 	./node_modules/.bin/lerna bootstrap
-	# remove all existing babel-runtimes and use the top-level babel-runtime
-	rm -rf packages/*/node_modules/babel-runtime
 	make build
 	cd packages/babel-runtime; \
+	npm install; \
 	node scripts/build-dist.js