This is all minor stuff: unreachable debug code (that should be commented-out
instead of in an 'if False:' block), unnecessary 'pass' and 'global'
statements, redundantly-initialized variables. No behavior changes. Nothing
here was actually broken, it just looked suspicious to the static analysis at
https://lgtm.com/projects/g/tahoe-lafs/tahoe-lafs/alerts/?mode=list .
* replace "last_details" with "non_connected_statuses" dict
* rename "last_connection_summary" to just "summary"
* for connected servers, show other hints in a tooltip
* for not-yet-connected servers, show all hints in a list
* build the list (in STAN) on the server side, not using IContainer
