Revert "Switch from zsh to fish"

This reverts commit c03a859068c57eed3ec1c4c93c4e6d38d36c7525.

Conflicts:
	fish/fishrc.symlink
	fish/prompt.fish
	go/go.fish
	system/path.fish
Revert "Tell Vim to use regular sh for it's shell"

This reverts commit e6fdd5197dff9802709b225b7e623d3b70d07615.
Revert "Tell Tmux to spin up fish instances"

This reverts commit 1f1842367014aaca9c115b53e33a03f5149ac4b4.
Remove fish module