fixes https://github.com/TryGhost/Toolbox/issues/459
- in the situation where the `yarn dev` command fails, it pumps out a
massive error message, which is incredibly distracting to the dev
experience
- this changes the output to just be a log line with some suggestions on
how to fix it
- I lowered the code coverage on the repo to the point where
it started failing because I added a new export to the config library
- this wasn't easy to add tests for because the existing config tests
use the loader directly and not the library export
- instead, I'm just going to make the dev script access the loader, and
make a note to clean this up in the future when we pull out the config
module
- because the cwd of `.github/dev.js` is not `ghost/core`, it doesn't
pick up config.local.json files, so any configuration you set in there
isn't applied
- this meant that developers with HTTPS configured locally couldn't use
`--stripe` because it wouldn't configure the Stripe listening URL
correctly
- this adds an exports to the config lib to allow passing options in,
which I then utilize to pass the directory that config resides in
- this should fix the aforementioned problem with HTTPS
refs https://github.com/TryGhost/Toolbox/issues/426
- this adds support for `--portal` in `yarn dev` to support the upcoming
migration of Portal into the monorepo
- also adds the Portal folder to the ignorelist for nodemon so Ghost
doesn't bootloop
refs https://github.com/TryGhost/Toolbox/issues/426
- we're going to need to support more complex combinations of dev
commands soon, with other packages optionally running and env
variables being altered
- this command pulls out a lot of the dev env scripting into a single
scripts
- also cleans up the use of grunt-shell so we can remove the dependency
