Revert "zsh: Set TERMINAL to urxvt"

This reverts commit fb1d54bee7abc3ac46a81092a1c03a2c36b54e54.
zsh: Remove unused vi bindings
zsh: Remove unused env vars
zsh: Merge zpreztorc from upstream
zsh: Case-sensitive completion and history lookup
zsh: Use prezto ssh module instead of keychain
Remove vim dotfiles
makefile: Remove vim
tmux: Remove unused vi bindings