Organism alarms: always trim the alarms log

Addresses #276
Core: always trim the history log

Addresses #276
Organism alarms: save log limit in database

Addresses #37
Core: reorder DBHistory init parameters
Core: fix bug in history (change the arguments passed to Item)
Core: limit line length
Core: leave recent history actions temporarily
Organism alarms: introduce new options

Addresses #276
Organism alarms: leave recent alarm log entries temporarily

Fixes #276