nix run: Respect propagated-user-env-packages
nix run: Respect propagated-user-env-packages

Also, add $path/bin to $PATH even if it doesn't exist. This makes
'man' work properly (since it looks for ../share/man relative to $PATH
entries).

peti/nix,vcunat/nix,peti/nix,rycee/nix,NixOS/nix,peti/nix,ehmry/nix,vcunat/nix,peti/nix,ehmry/nix,NixOS/nix,dtzWill/nix,dtzWill/nix,dtzWill/nix,zimbatm/nix,rycee/nix,ehmry/nix,peti/nix,layus/nix,dtzWill/nix,NixOS/nix,rycee/nix,layus/nix,ehmry/nix,ehmry/nix,vcunat/nix,zimbatm/nix,layus/nix,pikajude/nix,zimbatm/nix,rycee/nix,pikajude/nix,dtzWill/nix,ehmry/nix,vcunat/nix,pikajude/nix,layus/nix,NixOS/nix,zimbatm/nix,NixOS/nix,rycee/nix,layus/nix