Support most non-minion modifiers

[brather1ng]

With entering computation beta, I think we should already support most modifiers.

This excludes minion support because that's not an easy task. It also excludes modifiers that don't provide any value to the user or are niche enough that they can be implemented later on.

It includes the other two current limitations of the engine (besides minions): item-inherent skills and socketed skill modifiers.

• Support most skills
• Secondary skills
• Socketed gem modifiers
• Item-inherent skills
• Support most item modifiers