Revert "zsh arch- check if zsh is installed before trying to start it"

This reverts commit 4519b13d1ccc700e1af09f5fd3e804396d00a568.
Revert "ohmyzsh arch- run tmux if present"

This reverts commit 0f513d99311ff21d42287b2b6d29528e6f2173f8.