Fixed: Early Bird Bonuses were factored into Challenge mode popups by mistake.

Fixed: Default string for Challenge mode was not set correctly.

Fixed: Multi-kills would not handle Early Bird Bonuses correctly.

Replaced XGParamTag with new Metadata OldState logic.

Initial commit.

Overrides X2Action_ChallengeScoreUpdate and uses XGParamTags to work out the Early Bird Bonus.