Add other nyan cats to readme

[jgkamat]

I found atom-nyancat, so I decided to add it to the readme.

I also made a clone of this for qutebrowser, let me know if that dosen't qualify as an 'editor' though, and I'll remove it :P

Thanks for cementing the nyan into my life for the rest of time :)

[TeMPOraL]

Thanks!