[Tails-dev] [review'n'merge] remove obsolete page

Hello, I discover that the old donate page still exist (and is still
translatable)!
I also remove an obsolete part in a news.

Please review and merge.

Repo: https://git-tails.immerda.ch/xin/tails/
Branch: remove_old_donate_page
Last Commit: b164ce733db0bd369f68504e4e620eb9a00c43e9

Cheers.
xin