[Feature] Add Browser-update.org Banner

[ssteigen]

Notify visitors to update their browser to the latest version. https://browser-update.org

<script> 
var $buoop = {required:{e:-1,f:-1,o:-1,s:-1,c:-1},insecure:true,api:2020.03 }; 
function $buo_f(){ 
 var e = document.createElement("script"); 
 e.src = "//browser-update.org/update.min.js"; 
 document.body.appendChild(e);
};
try {document.addEventListener("DOMContentLoaded", $buo_f,false)}
catch(e){window.attachEvent("onload", $buo_f)}
</script>

[ExperiencersInternational]

I was going to do that in pull request #11. Minimum browsers should be 1st browser for that type that supports the site full e.g. e:12 OR 79 recommended for edge

[ssteigen]

I was going to do that in pull request #11 I think.

Looks like your PR had some extra stuff in it. I couldn't figure out how to clean it up, so I opened a new PR.

[ExperiencersInternational]

Yeah I didn't know how to clean it out neither.

[ExperiencersInternational]

Also it would be cool if you add a button to share to social media or even do mobile apps which I'm trying out now.

[ExperiencersInternational]

Using my repo, site doesn't load properly on chrome 44 so for the chrome category it needs to be newer than that.

[ExperiencersInternational]

Chrome 55 works so in chrome area, best in between 44-55 for chrome category.