Make the website mobile-friendly

[eXpl0it3r]

Currently the website is "usable" on mobile phone with zooming, but it's not exactly mobile friendly.

• Stack sections on mobile instead of showing it side-by-side
• Stack buttons on mobile instead of showing it side-by-side
• Make the menu usable on mobile either by just making it bigger and/or adding a hamburger menu navigation
• Make the tutorials work on mobile

The forum is IMHO best used with Tapatalk, but maybe there's a mobile theme somewhere, otherwise, I wouldn't really put in any effort in making it mobile friendly.

[eXpl0it3r]

See also #171