Watch method to proxy to chokidar

[phated]

We need to update the watch method for gulp 4 to just use chokidar directly since vinyl-fs is removing the watch syntax in 2.0 (as per gulpjs/vinyl-fs#92)

I know @es128 has mentioned he be able to help with this task.

[es128]

Yup I owe you a PR for this

[ddprrt]

I had a look into it. How should it behave with the different API. e.g. chokikdar's .close would equal .end. Chokidar does not feature an event object, but returns file stats. Adapt tests and feature a new API, or move to the new API and update all the docs?

[phated]

@ddprrt the watch API is going to be a tiny facade over chokidar's watch. We don't plan to have backward-compat with gulp 3.9's watch

[phated]

The chokidar switch has been made (in the 4.0 branch)!!!! Closing!