GapMAX

Custom components may cause memory leak.[BUG]

3

## Environment "formiojs": "^4.0.0-rc.21", "react": "16.8.2", "react-formio": "^4.2.6", ## Steps to Reproduce Run official example(https://github.com/formio/react-app-starterkit) and go into #/form/create, drag and Drop React example compoennt, and then open react dev...

换成lodash-es是否可以减少包体积？