Update .gitconfig

* Edit aliases : +pl, +cpick, -cb, -current-branch
* Add global .gitignore : ~/.gitignore
Update .zshrc.osx

* Edit aliases
* Disable pyenv, phenv
Change colors in pry
Change gem sources to ~/dev/src/gems
Add git subcommand: ignore, cancel

ignore is from: http://qiita.com/items/f8c27d37052e2e573504
cancel is from: http://d.hatena.ne.jp/thinca/20120924/1348491052
Update tmux.conf
Add vimerl for Erlang
Update RUBY_CONFIGURE_OPTS for ruby-build
Clean up .zshrc*