Fix docker debian image locale error !

Readme.md

Just run the commands below and have fun!

$ apt-get update && DEBIAN_FRONTEND=noninteractive apt-get install -y locales
$ sed -i -e 's/# en_US.UTF-8 UTF-8/en_US.UTF-8 UTF-8/' /etc/locale.gen &&     echo 'LANG="en_US.UTF-8"'>/etc/default/locale &&     dpkg-reconfigure --frontend=noninteractive locales &&     update-locale LANG=en_US.UTF-8
$ export LANG=en_US.UTF-8

More details here: http://stackoverflow.com/questions/28405902/how-to-set-the-locale-inside-a-docker-container