This doesn't embed ALL the options for the ssh client, but I based it
on options I use regularly. Here's an example usage extracted and
edited from my home.nix:
```nix
programs.ssh = {
enable = true;
forwardAgent = true;
controlMaster = "auto";
hosts = {
"something.blah.edu" = {
port = 1024;
user = "cleague";
identitiesOnly = true;
};
"host1 host2 host2.net host2.com" = {
port = 7422;
hostname = "example.com";
serverAliveInterval = 60;
};
"lucian" = {
forwardX11 = true;
forwardX11Trusted = true;
checkHostIP = false;
};
};
};
```
