Interactive config should employ better algorithm to detect installation command in CI config files

[honzajavorek]

Interactive config currently just checks whether the npm install -g dredd isn't already present in the TravisCI or Circle CI configuration file. It should be more benevolent in checking what's present (npm install dredd, npm install -g dredd@...) and it should be more strict in what will be passed to the output (npm install -g dredd@version if command uses pinned version or npm install -g dredd@stable otherwise).

[honzajavorek]

• if package.json is present and dredd is not there, offer adding it
  • yes?
    • run npm install dredd --no-optional --save-dev
    • if running dredd is not present in the CI config, add npx dredd to the CI config
    • ensure the CI config contains something like npm install
• else
  • ensure dredd in globally installed in the CI config npm install dredd@version --no-optional --global
  • if running dredd is not present in the CI config, add dredd to the CI config

Indepotent!

[honzajavorek]

Okay, I gave it a bit of focus and it's way too complicated. Programmatic editing of CI configurations is a difficult task full of assumptions. I'll go with an easier solution and let's see how that works, anyone is welcome to improve my work and to catch corner cases, afterwards.