Add bindings to sd_nofify* functions

[nemanja-boric-sociomantic]

https://github.com/dlang/druntime/pull/1848

[mihails-strasuns-sociomantic]

As discussed in chat, the main question is if such bindings do belong to runtime modules at all (being bindings to specific library/system and not general platform thing)

[leandro-lucarella-sociomantic]

I think systemd and the linux kernel are getting very close, so it doesn't look completely crazy to me to be in the runtime. I would see how it goes in druntime. If they want it there, then we put it in here, otherwise I would put it in ocean.

[leandro-lucarella-sociomantic]

I actually think this is more something for Ocean, I don't think it belongs to druntime. I would close both PRs and add it to ocean and even maybe adding a thin, more-Dish, wrapper (and eventually integrate it to the App framework).

[nemanja-boric-sociomantic]

Fair enough.