Consider adding a tooltip to the disabled "Invited to this Room" button

[anoadragon453]

Description

When you don't have the power level to invite another user to a room or otherwise aren't able to do so, the button is disabled. This is great, but users will inevitably start asking "why???" in the room.

It'd be nice if a tooltip were added that said the reason, such as "You power level is not high enough to invite users to this room".

[scruloose]

Would hiding the button entirely from users who don't have the power level to use it make sense as an alternative?

[t3chguy]

IMO hiding would cause more confusion

@lampholder thoughts?