Redesign: Support for room tags

[madduck]

Just gave /experimental a whirl, and the first thing I notice is that rooms aren't listed under tags anymore, as has been the case for the standard, as well as /develop release. Please support room tags, ideally not just read-only (i.e. display rooms in the list accordingly), but also give people a means to add/remove tags to rooms, and to manage existing tags (#1373).

[PureTryOut]

Interesting, room tags show up and work fine for me. I do not like that you have to resize each room tag individually instead of just being able to scroll through the whole room list, but I guess that should be in a different issue.

[aaronraimist]

They are back in 1.0.0 under a labs flag. #8723 is the issue for enabling it by default and getting rid of the labs flag.