[tor-dev] Building meek-server with Go 1.11.5

Attached is a script for building meek-server. I used this for completing #29171. The newest version of Go is only available in Sid and Buster[0], so this script creates a Buster environment and installs the dependencies.

The script assumes debootstrap and sudo are installed (and you have necessary privilege). As of today, a Debian Buster system should create a reproducible binary with a SHA-256 digest 6e242798f861308083e54bc0ca3989a03b0818475e9b6df4589ced10c7e3aadc (confirmed over multi-path builds).

This is simply an FYI, in case anyone else want so to use it.

- Matt

[0] https://security-tracker.debian.org/tracker/source-package/golang-1.11