Rework learning mechanics, following issue #613

Implements items 1 through 5, from issue #613.
Added American Flag Spawn for School
Added American Flag
Added GET_FLAG
Added Find Flag
Added find flag dialogue
Added Cathedral
Added Cathedral
Added Cathedral

The towers will get filled in with the addition of z-levels...
Added the small relic for the cathedral fetch quest
Added Corporate Accounting Ledger, Patient Records, and National Weather Transcripts
Added dialogue for 4 of the new missions
Added new missions...
Added new missions to mission_id
Added spawning of unique items for quests
Added Corporate Accounting Ledger, Patient Records, and National Weather Transcripts
Added Kill Jabberwock
Adding place_jabberwock
Added Kill Jabberwock
Added Kill Jabberwock mission