Load OMZ in proper order

We need to load OMZ’s config file, then OMZ, and then
load any other topic ZSH files. I’ve done a bit of
hackery to ensure this happens.
1) The configuration file for OMZ sets up and then
loads OMZ, so it’s always loaded with config set
2) This file has been renamed path.zsh to ensure that
it loads before any of the other topic.zsh files. It’s not
technically a path modification, but I doubt anyone would
have path problems due to this (unless their OMZ is really
wacky)
Remove non-OMZ prompt configuration

Configuring the prompt in topic files
overwrites anything that OMZ has previously
configured.

If you want to modify the prompt you’re using,
modify it at the source (e.g. inside OMZ)