Previously, some functions that conceptually belong to the connection needed to be in the Controller, since we didn't have a place to put them.
This fixes that by extending the Connection class in a similar way as we extend the Room class.
- Split the list into sections for "this devices", "verified devices", "unverified devices", and "devices without encryption support"
- Sort the lists by last activity
Also modernize the codebase where possible (e.g use required properties,
reorder properties, fix warnings, don't use Action when not needed)
Signed-off-by: Carl Schwan <carl@carlschwan.eu>
