Update links to HTTPS and remove Get Started button

[jonaharagon]

• Updated wiki link to https://...
• Removed white "Get Started!" button from navbar
• Updated irssi.org and quassel-irc.org links to https://... on contact page

[jonaharagon]

Deploy preview for opennic ready!

Built with commit 737cb09cd8e7f9fd81e125142cf472cf61151702

https://deploy-preview-56--opennic.netlify.com