#890 Bug in AbstractAI.getHintedRecruitmentValue

[Craig Lish]

Bug in AbstractAI.getHintedRecruitmentValue(CreatureType creature, Legion legion, List<IVariantHint.AIStyle> styles).
Only effects titan rectruitment value calculation.

The calculation for titan should have a + instead of a * since the default hinted value is 0.
<code>
return power * skill + VariantSupport.getHintedRecruitmentValueOffset(creature, styles);
</code>