Assert that atomic commands from cmdAtomicFilterCli are correctly visible
Rename constructors of PosAtomic
Ensure a faction always notices the death of its member

Also, let it notice HP increase/decrease, etc., even if the actor
is blind and numb and no other party member can see him. OTOH,
don't notice if such an actor is displaced, etc.
Let searching succeed already on the first attempt

Also, change the map of secrecy strength of tiles into a per-level
secrecy seed to be used later on.
Fix assertions about client managing previously seen things
Remove searching, but actors can open hidden doors instead
Fix double LoseActor when using stairs or dying