[INTERNAL] Update min Node.js version to >=8.5

RandomByte · RandomByte · commit 89b7f219279e · 2018-07-11T17:03:08.000+02:00
To allow usage of fs.copyFile() API
diff --git a/package.json b/package.json
@@ -14,7 +14,7 @@
 	],
 	"main": "index.js",
 	"engines": {
-		"node": ">= 8.3",
+		"node": ">= 8.5",
 		"npm": ">= 5"
 	},
 	"scripts": {
