Some new discovery story events

Fixes to discovery and other

New answer options to ju ahet contact event, probably chould cover all possibilities
Allow migration for caste will show only for empires with caste

Another pirate update

Balance, fixes and changes to drones and pirates

New traits

Fixes
New pirate event
Removed traits from trait codex mod, more traits to come instead

Fixed new event spam

New events for pirates

Fixes and new event for pirate