Deno version manager inspired by rbenv

1. Check out denoenv into any path (here is ${HOME}/.denoenv)

 $ git clone https://github.com/kaminchu/denoenv.git ~/.denoenv

2. Run install to compile

$ ~/.denoenv/install

3. Add ~/.denoenv/bin to your $PATH any way you like

$ echo 'export PATH="$HOME/.denoenv/bin:$PATH"' >> ~/.bash_profile