Remove `b` script about summoner

[chshersh]

The coloring and perl magic should be disabled for GHC >= 8.2.1. But also this should be added to stack.yaml:

ghc-options:
  "$locals": -fhide-source-paths

[chshersh]

Okay, I propose to do the following with this b script:

1. It makes sense only for older GHC and for multi-package projects. I think nobody cares about pretty output for GHC < 8.2.1 because such old GHCs are the default nowadays for creating new project.
2. We should add "$locals" to every stack.yaml file.
3. We should remove coloring from b script.