Add wayland clipboard support

[kamiyaa]

• change paste_keys() to return a &'static str instead of a String

Not sure how reliable cli_clipboard is but it seems to be working as intended.
The problem might be that rooster will require wayland protocols to be installed in order to compile now (on Linux)

Open to feedback

[conradkleinespel]

Hello @kamiyaa , thanks for your contribution !

I'm all for Wayland support, but reluctant of adding new dependencies because I can't review all of them for security. So instead of depending on cli-clipboard, would you mind making use of wl-clipboard (https://github.com/bugaevc/wl-clipboard), in the same way xsel / xclip are currently used ?

You'd need to:

• add code that detects if the user is using Wayland, if so, call to wl-clipboard instead of xsel/xclip
• in README.md, add instructions for how to install wl-clipboard for Wayland users

[kamiyaa]

Okay, I changed it to make use of wl-copy and users can force wayland to be checked first via XDG_SESSION_TYPE=wayland environment variable

[conradkleinespel]

@kamiyaa Looks great, thanks!

Would you mind reverting the changes to Cargo.lock please? Then I'll merge.

If you want to appear in the contributors' list, feel free to add yourself to it in README.md in alphabetical order.

[kamiyaa]

@conradkleinespel done!

[conradkleinespel]

Awesome, thanks a lot for your help !

[conradkleinespel]

@kamiyaa I just published this, along with other recent changes, as version 2.9.0 on crates.io and will update the Arch Linux package shortly as well. https://github.com/conradkleinespel/rooster/releases/tag/v2.9.0