Furthermore, the comparison page is mostly removed, as it was severly
outdated. It now links to more up-to-date comparisons.

Other (minor) changes:
- links to sourceforge are changed to links to github
- mentions of FLAC Frontend are removed
- made background colors slightly less pronounced
- fix homebrew link
- deduplicate news from homepage
- removed a few links from navbar, to aid mobile navigation
- remove mentions of XiphQt
- remove the 'Ask Apple for FLAC support in iTunes' page and links