Source prompt in zshrc.

Thoughtbot removed their own `zlogin` file, which fixed the
prompt-stomping problems that necessitated the `.local` version.

Also removing iTerm scripts that were executed by ControlPlane to switch
font sizes when jumping from mobile to big monitors. My adoption of tmux
has made my terminal sessions longer-lasting, which resulted in a lot of
frustrating inconsistency.
Clean up autocomplete / syntax checking.
resetdb alias.