Pull in a pre-built tarball of cmake 3.1.3 for the bots.

Built from:
45f4d3fa8a2f61cc092ae461aac4cac1bab4ac6706f98274ea7f314dd315c6d0  cmake-3.1.3.tar.gz

Also drop in an extraction script.

Change-Id: I3487e9d432290a7dbabf854b927412c58c35d12b
Reviewed-on: https://boringssl-review.googlesource.com/3492
Reviewed-by: Adam Langley <agl@google.com>
3 files changed