feat(read-chunk): module to read data from stream

@vates/read-chunk/README.md

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+<!-- DO NOT EDIT MANUALLY, THIS FILE HAS BEEN GENERATED -->
+
+# @vates/read-chunk [![Build Status](https://travis-ci.org/vatesfr/xen-orchestra.png?branch=master)](https://travis-ci.org/vatesfr/xen-orchestra)
+
+> Read a chunk of a Node stream
+
+## Install
+
+Installation of the [npm package](https://npmjs.org/package/@vates/read-chunk):
+
+```
+> npm install --save @vates/read-chunk
+```
+
+## Usage
+
+- returns the next available chunk of data
+- like `stream.read()`, a number of bytes can be specified
+- returns `null` if the stream has ended
+
+```js
+import { readChunk } from '@xen-orchestra/read-chunk'
+;(async () => {
+  let chunk
+  while ((chunk = await readChunk(stream, 1024)) !== null) {
+    // do something with chunk
+  }
+})()
+```
+
+## Contributions
+
+Contributions are _very_ welcomed, either on the documentation or on
+the code.
+
+You may:
+
+- report any [issue](https://github.com/vatesfr/xen-orchestra/issues)
+  you've encountered;
+- fork and create a pull request.
+
+## License
+
+ISC © [Vates SAS](https://vates.fr)

@vates/read-chunk/USAGE.md

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+- returns the next available chunk of data
+- like `stream.read()`, a number of bytes can be specified
+- returns `null` if the stream has ended
+
+```js
+import { readChunk } from '@xen-orchestra/read-chunk'
+;(async () => {
+  let chunk
+  while ((chunk = await readChunk(stream, 1024)) !== null) {
+    // do something with chunk
+  }
+})()
+```

@vates/read-chunk/index.js

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+export const readChunk = (stream, size) =>
+  new Promise((resolve, reject) => {
+    function onEnd() {
+      resolve(null)
+      removeListeners()
+    }
+    function onError(error) {
+      reject(error)
+      removeListeners()
+    }
+    function onReadable() {
+      const data = stream.read(size)
+      if (data !== null) {
+        resolve(data)
+        removeListeners()
+      }
+    }
+    function removeListeners() {
+      stream.removeListener('end', onEnd)
+      stream.removeListener('error', onError)
+      stream.removeListener('readable', onReadable)
+    }
+    stream.on('end', onEnd)
+    stream.on('error', onError)
+    stream.on('readable', onReadable)
+    onReadable()
+  })

@vates/read-chunk/package.json

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+{
+  "private": false,
+  "name": "@vates/read-chunk",
+  "homepage": "https://github.com/vatesfr/xen-orchestra/tree/master/@vates/read-chunk",
+  "description": "Read a chunk of a Node stream",
+  "license": "ISC",
+  "keywords": [
+    "async",
+    "chunk",
+    "data",
+    "node",
+    "promise",
+    "read",
+    "stream"
+  ],
+  "bugs": "https://github.com/vatesfr/xen-orchestra/issues",
+  "repository": {
+    "directory": "@vates/read-chunk",
+    "type": "git",
+    "url": "https://github.com/vatesfr/xen-orchestra.git"
+  },
+  "version": "0.0.0",
+  "engines": {
+    "node": ">=8.10"
+  },
+  "scripts": {
+    "postversion": "npm publish --access public"
+  }
+}