Analyze the possibility of autoloading functions in Zsh

Zsh and shells like ksh have a builtin called `autoload` that can be used to load functions from `$FPATH` into memory. I remember reading somewhere that a reference would be loaded into memory, but not the function definition, or something along those lines.

If it can speed up the startup process for Zsh, as it has to load all the files in its configuration (not that it matters too much when it's <1s), change functions so they're in their own files somewhere under `$FPATH`.