Add Action_Success_Actor/Target_Kill_Pct effects

[danau]

Feature request to add the following actions (similar to the existing Action_Success_Actor_Move_Cost and Action_Success_Target_Move_Cost effects);

Code: Select all

Action_Success_Actor_Kill_Pct
    The chance (in percent) that a unit dies when it successfully performs an
    action. Evaluated and done after the action is successfully completed.

Action_Success_Target_Kill_Pct
    The chance (in percent) that a unit dies when someone successfully performs
    an action on it. Evaluated and done after the action is successfully
    completed. Only supported for actions that targets an individual unit.
    (See doc/README.actions)

The Action_Success_Actor_Kill_Pct effect effectively allows any action to be placed as a suicide action for certain units or under certain conditions. This for example allows a "Cluster Missile" unit to attack using Bombard (Cluster Missile Attack) while still allowing the missile to be used-up in the attack.
This effect can also be used as a risk; for example to give "investigate city" a 10% chance of the investigating unit to die after the investigation is done.

The Action_Success_Target_Kill_Pct effect could for example also be used on the "Heal" action, allowing heal to have a 10 percent chance of killing the target that was to be healed.