Add multiple permissions at once.

It takes minutes settings permissions when done step by step.

For https://github.com/build2be/drupal-rest-test I need to set 30 permissions which currently takes 5:20 mins which is due to the `drush_drupal_cache_clear_all()`. With the patch it is reduced to 1:29 mins but that's due to my bad script in mentioned project.

> 30 calls in 5:20 : ~ 11 secs per call
> 8 calls in 1:29 : ~ 11 sec per call