Weakpoints can use conditions and eocs

[GuardianDll]

Summary

None

Purpose of change

Json power

Describe the solution

Move npc_opinion into it's own header, to fix circular dependency (thanks Snup)
Add condition field for weakpoints
Replace required_effects and disabled_by fields with condition
Add effect_on_conditions field

Testing

pseudo_weakpoint_mon with no changes

pseudo_weakpoint_mon with condition math: n_hp(all) > 5000

pseudo_weakpoint_mon with

"effects": [ { "effect_on_conditions": [ "EOC_TEST" ], "chance": 50, "message": "The %s is disorientated." } ]

  {
    "type": "effect_on_condition",
    "id": "EOC_TEST",
    "effect": [
      { "u_message": "u_message, u_name: <u_name>, npc_name: <npc_name>" },
      { "message": "message, u_name: <u_name>, npc_name: <npc_name>" }
    ]
  },