Flag to automatically run tests on yogi build

[hatched]

It would be great if I could have tests auto run on build so I could do something like

yogi build --watch --test

[davglass]

yogi@0.0.66 added --test to yogi build, but --watch doesn't work just yet since the processes are separate yogi doesn't know when a build has been shifted, it's waiting on the shifter process to exit which won't happen on a --watch. I would have to redesign the way shifter if used under the hood to get this to work.