If a user has set core.autocrlf = true (which shouldn't ever be used on
OS X, but alas...), a subsequent `brew update` will check out files with
CRLF line endings. Setting core.autocrlf = false in Homebrew's repo
config will override this global setting, and let us check out files
with their in-repository line endings.
Signed-off-by: Jack Nagel <jacknagel@gmail.com>