Drop in Go toolchain bootstrap scripts for the bots.

Severely trimmed version of Chrome infra's scripts.

Change-Id: I378b68be670b74fe0518de5d66e0aa8b2d709f26
Reviewed-on: https://boringssl-review.googlesource.com/3491
Reviewed-by: Adam Langley <agl@google.com>
3 files changed