[PATCH 3 of 3] util: replace file I/O with readfile

[Sean Farley]

Bryan O'Sullivan <bos at serpentine.com> writes:

> # HG changeset patch
> # User Bryan O'Sullivan <bryano at fb.com>
> # Date 1452644179 28800
> #      Tue Jan 12 16:16:19 2016 -0800
> # Node ID 6200e4379675b401551c08e19f16f32f6f55e97c
> # Parent  bdda0258d3884e81b9b80ca71669934d237be54c
> util: replace file I/O with readfile

Yep, looks good to me.