Configuration for shell

• dot files set without symlinks
• alias git to 'checkout' and use checkout to manage config files
• setup done via script as bash <(curl -s http://openbracket.com/config-install)
• add target environment public key to github

Inspired by

https://developer.atlassian.com/blog/2016/02/best-way-to-store-dotfiles-git-bare-repo/