Add example: SSH config to a timerd config file

[chx]

As noted in https://superuser.com/a/1142813/41259 SSH not only has an include file feature but also "Include directive may appear inside a Match or Host block to perform conditional inclusion." so the easiest way to integrate with SSH is to write the "Hostname ...." section into a file periodically. Currently the examples folder is about the server, perhaps move these examples into a server folder and add a client directory with a client side timerd example.

[mikroskeem]

WIP in feature/ssh-client-config-gen branch

Does not support multiple hosts yet clearly, but shouldn't be hard to implement with a little bit of shell scripting.

Host domain.tld
    Include /var/run/tosh/host-config

Picked /var/run to prevent generating unnecessary disk I/o (/var/run sits on tmpfs these days)

Technically can add user timer as well, would write file to a path under XDG_RUNTIME_DIR.