Changes from webhint

[r0mflip]

Required updates:

• alt tags for all img tags
• noopener noreferrer for all external/internal anchor tags
• remove all <meta http-equiv="X-UA-Compatible" content="IE=edge"> tags

Have a look at

• https://webhint.io/scanner/3a5bbf9f-9e38-4107-bd9a-095e32feb2d1
• https://webhint.io/scanner/4d5055e0-6bd8-4fcb-b975-8a24983e49e8

[me-diru]

I am interested in doing this.