a6abec9c66
system-sendmail allows all sendmail's to be auto-detected, including on non-NixOS systems. This is, to me, a better UX than having to manually override the sendmailPath argument. In exchange, it is a breach of retro-compatibility. Given right now I can't see any uses for sendmailPath other than what is supported by system-sendmail, I didn't keep it, but it'd be possible to allow sendmailPath to override the choice of sendmail from system-sendmail.
*** NixOS *** NixOS is a Linux distribution based on the purely functional package management system Nix. More information can be found at http://nixos.org/nixos and in the manual in doc/manual.