Improve readme and --help

[lydell]

• Recommend installing locally. Fixes Recommend local rather than global install #249.
• Move more common flags first, both in the readme and in --help.
• Sync the descriptions between the readme and --help.
• Try to explain the difference between node-test-runner and elm-explorations/test.
• Document where to put your tests.
• Various other little tweaks to try to be more helpful.

PR for elm-explorations/test: elm-explorations/test#160

We should also update the repo description because it currently says:

Runs elm-test suites from Node.js. Get it with npm install -g elm-test

[harrysarson]

Hi yes, I am not sure how to review this. I dunno how people do code review on prose.

Stylistically I have a preference for avoiding the passive voice. (So "it is recommended" would become "we recommend".)

[lydell]

If you like it overall, feel free to make whatever tweaks you like and push them to my branch if you want.

For broader changes, feel free to suggest things like “remove this section”, “this is good but that is more important so it should be more prominent” or “I see what problems you tried to solve but I’d like to phrase things a completely different way”. Or push big changes to my branch if you feel like it. Or another branch based on mine.

Or review any way you like. I don’t mind. 😄

Edit: Also, if “please avoid passive voice” is your only piece of feedback I can try to fix it myself too.

[harrysarson]

I put some comments. A lot are very minor and almost all are subjective so feel free to push back.

[harrysarson]

I am happy, will just wait and see if anyone else wants to take a look before we merge.