disable omz autoupdate

adds a good 0.1s to startup time, I can upgrade manually
reenable autotitle

new tab setting in terminal seems to depend on it.  TODO: look into
making window title less ugly.
enable waiting dots

blingy, why not
type is apparently safer than which

built-in instead of external command
add brew cask plugin

since i rely on it a lot now
npm plugin is super slow

adds a full 0.2ms to startup time (disabling makes time zsh -i -c exit
go from 0.3ms to 0.1ms on iMac)