Implement default config for pre and post build keys (#496)

Author: PeteBishwhip

config/nativephp.php

@@ -125,4 +125,15 @@
             'timeout' => 60,
         ],
     ],
+
+    /**
+     * Define your own scripts to run before and after the build process.
+     */
+    'prebuild' => [
+        // 'npm run build',
+    ],
+
+    'postbuild' => [
+        // 'rm -rf public/build',
+    ],
 ];