Global music play command?

I’ve seen that there are like those commands where you can play a sound from a soundpath which everyone can hear.

Now I am wondering how to make the same thing just with youtube links or any other media link.
Everyone should be able to hear it when the command ran means it does a cind of data streaming for everyone but they should be able to change the volume and also be able to close it.

Is this possible?
How does it work?

I personally use this library, and it works fine for youtube and is flexible.

You can stop the sound, change the volume, start from a certain timestamp ect.

Wait does this add any commands?

Edit:

As I can see as soon as I put this inside addons I can use the functions from the API to make commands for it and that what I wanted, am I right?

I used the SoundCloud API here:
http://forum.facepunch.com/showthread.php?t=1535406

Please don’t use my API key if you make your own variation though.

I have including problems.

I put it inside the addons folder as medialib/medialib.lua

and I need to include it in one of my gamemode files.

Then don’t publicly share your API key…

you maybe know how to include?

I get errors

Can you actually include something out of the file?