Remove obviated site.db implicits in models
Add Slot.idents because it seems useful

Really this is just a start in exploring record dimensions.
Fix lingering warning about overloaded result
Merge remote-tracking branch 'github/gui'
Add permission checks for study page assets
Show classification on assets rather than consent

Classification is the more relevant and directly assigned attribute, though it
should perhaps be described as "type" or something.
Add record list widget to slot and asset
Cache and optimize Entity.delegated; fix doc
Merge remote-tracking branch 'remotes/origin/master' into gui
Merge remote-tracking branch 'remotes/origin/master' into gui