git: Add a script which will download the current version of binary files.

This script will be run by a git hook and download large(ish) binary files
from google storage. By not having the history of those files stored in git,
we avoid having to download enough information to recreate obsolete versions
of those files every time a checkout is created.

Change-Id: I6bc34da60b3f2eb74e4101e321aa29a9af4ca08a
1 file changed