Group of users that can edit

[JammyDodger]

这个有一个小的更新——有一些关于群组启用设置的讨论，这可能会涵盖此用例：

Separate 'trusted users can edit others' setting for trust levels 3 & 4

I am generally warm to adding this fidelity though I would prefer to just “de-trust level” these settings if we do a split and change them so they are group based. edit_all_topic_groups (default: trust_level_3) edit_all_post_groups (default: trust_level_4) This also automatically add a bunch of extra flexibility and I feel the name of the settings are fairly clear. @mcwumbly thoughts. Not sure when we can slot this, it may be a candidate for pr-welcome.