build a golang cross-compile toolchain for ARM on Linux

1. Download the latest golang source: wget https://go.googlecode.com/files/go1.2.1.src.tar.gz
2. export GOOS=linux
3. export GOARCH=arm
4. export GOARM=7 (find out your ARM version based on the ARM processor). This step can be skipped as long as you know your ARM version is not 5.
5. export GOROOT=/home/me/go (set this to where your untarred go directory)
6. cd go/src; ./make.bash

There you have it.