docs: update for 2.0 (#42)

BREAKING CHANGE: commit ead1083 dropped support for Node < 8.

* chore: add CONTRIBUTING/support docs
* docs: put building docs after API docs
* docs: promisify API docs

CONTRIBUTING.md

@@ -0,0 +1,18 @@
+# Contributing to `node-rcedit`
+
+## Code of Conduct
+
+This project is a part of the Electron ecosystem. As such, all contributions to this project follow [Electron's code of conduct](https://github.com/electron/electron/blob/master/CODE_OF_CONDUCT.md)
+where appropriate.
+
+## Bugs / Feature Requests
+
+Most bugs and feature requests in `node-rcedit` can be attributed to
+[`rcedit`](https://github.com/electron/rcedit) itself. Please look in that project's issue tracker
+first before filing an issue here.
+
+## Releases
+
+`node-rcedit` uses `semantic-release` plus a plugin named "continuous factor authentication" to
+publish new releases to NPM. When a pull request is merged, a new release is queued in CircleCI, and
+a member of the Electron [Docs & Tools Working Group](https://github.com/electron/governance/tree/master/wg-docs-tools) needs to approve it.

README.md

@@ -5,21 +5,16 @@
 
 Node module to edit resources of Windows executables.
 
-## Building
-
-* Clone the repository
-* Run `npm install`
-* Run `npm test` to run the tests
-
 ## Docs
 
-```js
-var rcedit = require('rcedit')
+```javascript
+const rcedit = require('rcedit')
 ```
+
 On platforms other than Windows, you will need to have [Wine](http://winehq.org)
 1.6 or later installed and in the system path.
 
-### `rcedit(exePath, options, callback)`
+### `async rcedit(exePath, options)`
 
 `exePath` is the path to the Windows executable to be modified.
 
@@ -38,5 +33,10 @@ On platforms other than Windows, you will need to have [Wine](http://winehq.org)
   See [here](https://msdn.microsoft.com/en-us/library/windows/desktop/aa374191.aspx)
   for more details.
 
-`callback` is the `Function` called when the command completes. The function
-signature is `function (error)`.
+Returns a `Promise` with no value.
+
+## Building
+
+* Clone the repository
+* Run `npm install`
+* Run `npm test` to run the tests

SUPPORT.md

@@ -0,0 +1,9 @@
+# Support for `node-rcedit`
+
+## Troubleshooting
+
+This module uses the [`debug`](https://npm.im/debug) module to print out debugging information. To
+use it, consult your operating system's documentation on setting environment variables _([Windows
+notes](https://github.com/visionmedia/debug#windows-command-prompt-notes))_. Set the `DEBUG`
+environment variable to `rcedit`, and it will print out information, including any `STDERR` output
+from `rcedit.exe`.