[Merge] ~vorlon/casper:cleanup into casper:main

[Steve Langasek]

> The UB team will make sure that we will drop language-selector.desktop from
> our budgie-desktop-environment package early in the next cycle ... so if
> that helps cleanup things further.

Thanks, it does.  I've pushed an additional commit to drop the 35fix_language_selector hook entirely, since this is for post-mantic and it will no longer be needed at all.
-- 
https://code.launchpad.net/~vorlon/casper/+git/casper/+merge/452496
Your team Unity7 Maintainers Team is requested to review the proposed merge of ~vorlon/casper:cleanup into casper:main.