KazuhiroItoh

I have created a prototype version for the purpose of verifying the [UI Module design notes](https://github.com/node-red-hitachi/designs/tree/ui-module/designs/ui-module). This prototype implements the addition of Config nodes and support for existing functions, and...

Add design note of flow testing extensions & GUI testing

3

This PR adds plugin extensions and GUI testing function to the [flow testing](https://github.com/node-red/designs/tree/master/designs/flow-testing) design notes.

- [x] Bugfix (non-breaking change which fixes an issue) - [ ] New feature (non-breaking change which adds functionality) ## Proposed changes Improved the error message when callback is not...

I have corrected README.md, so please merge it.