Please allow customizing the build folder

Created by: lemiesz

Is your proposal related to a problem?

Where I work we can not use native npm. We have an internal company wide build system for managing dependencies across different language, os build, applications, etc. Its pretty complicated and I wont get into why its necessary.

However this system uses the /build folder for its own artifacts. Creating conflicts with the CRA build. I dont want to have to eject and manage my own webpack distribution just to have the abliity to rename an outfolder

Describe the solution you'd like

`react-scripts build --out "/dist"

This would name the output folder dist instead of build.