add create-react-app --info

[tabrindle]

This issue template seems to reserve a lot of space for trying to replicate and lock down issues from differing environments. Generally we want to make the process easier to ensure we get quality bug reports, so if the maintainers of the project agree, I'd like to integrate my envinfo package into CRA, the same way I already have for react-native.

Something like this:

create-react-app --info in a project will yield something like this:

Environment:
  OS:  macOS Sierra 10.12.4
  Node:  v7.10.0
  Yarn:  0.24.5
  npm:  4.2.0
Packages:
  react:  16.0.0-alpha.6
  jest:  ^20.0.4
  eslint:  ^3.19.0
  babel-polyfill:  ^6.23.0

I can add/subtract things from this report, and even nifty things like add auto add to clipboard.

Thoughts?

[bondz]

This would help with the environment section of the issue template

### Environment

<!--
  Please fill in all the relevant fields by running these commands in terminal.
-->

1. `node -v`: 
2. `npm -v`:
3. `yarn --version` (if you use Yarn):
4. `npm ls react-scripts` (if you haven’t ejected): 

Then, specify:

1. Operating system:
2. Browser and version (if relevant):

But would require an update to CRA itself to work.

[tabrindle]

Indeed - react native already has similar and it has worked amazingly well - you can see it in action in their issues. They even have a bot to auto close issues missing the template and environment.

The only additional thing they would have to add is browser+version.

react-native had the same issue where it was only available starting on version 0.48, but it was a good reason to get people to upgrade, and frequently solved their problem before even fully reporting the issue.

If we believe it's worth it, I will make 2 PRs - one to add the CLI command, then another to add the updated instructions to the issue template, once the first PR is merged and there has been some time to update.

[bondz]

Personally, I like it.

Also #3385 seems to be going the direction of adding a flag like this one.

cc @Timer

[tabrindle]

I have a PR for the change to the CLI - #3408. I think we close this issue once that and my changes to the issue template get merged.

[tabrindle]

I think its safe to close this issue now - both the implementation and docs are merged!
Thanks guys!