package,readme: bump minimum node version requirement to v10

Author: mscdex

README.md

@@ -8,7 +8,7 @@ A simple [node.js](https://nodejs.org) binding to [cpu_features](https://github.
 Requirements
 ============
 
-* [node.js](http://nodejs.org/) -- v8.0.0 or newer
+* [node.js](http://nodejs.org/) -- v10.0.0 or newer
 * An appropriate build environment -- see [node-gyp's documentation](https://github.com/nodejs/node-gyp/blob/master/README.md)
 
 

package.json

@@ -19,7 +19,7 @@
     "lint:fix": "npm run lint -- --fix"
   },
   "engines": {
-    "node": ">=8.0.0"
+    "node": ">=10.0.0"
   },
   "keywords": [
     "cpu",