Fix go get "you are not currently on a branch" error

fix.sh

#!/bin/bash

# https://groups.google.com/forum/#!topic/golang-nuts/t9dLLVwsMlM
# run in a directory of git repos e.g. ~/go/src/golang.org/x

 for dir in ./*; do # use ./*/* for two-level directories eg ~/go/src/github.com
   pushd $dir;
   git pull --ff-only origin master;
   popd;
done