Added Github star button

[michalv8]

Used buttons from https://ghbtns.com/

Todo:

• [x] fix mobile styles

[danon]

That will slow initial loading time of the webpage, potentially lowering seo.

Maybe it would be better to hook up to 'load' event, and then dynamically add the <iframe/> to DOM, to load it afterwars.

[danon]

Spowodowało: https://4programmers.net/Forum/Coyote/369777-powiadomienia?p=1926747#id1926747