Add instructions in the readme for buildign the dev stack
Add instructions in the readme for buildign the dev stack

NSLS-II/auto-build-tagged-recipes,NSLS-II/auto-build-tagged-recipes,NSLS-II/lightsource2-recipes,NSLS-II/lightsource2-recipes,NSLS-II/lightsource2-recipes,NSLS-II/lightsource2-recipes