[DynamicLevies] test and balancing suite

[zijistark]

• [ ] A maintenance event that runs for all counts and barons, checking whether they somehow have a primary title demesne law other than dynlevy_0 or none, respectively. Sends an alert to player if it happens, as this should never happen. [ Note that currently the baron case actually will "fail," but they'll be assigned dynlevy_0 always, which technically does no harm. ] Current design assumptions rest upon this never happening. If they do happen, send an alert to the player.
• [x] A console-triggered utility event invoked upon a character ID which displays their dynamic levy law in effect, hopefully displaying both the grade and levy law modifier.
• [X] Law calculator that makes it easy to assess any combination of PB laws with realm_size's consequent net vassal_levy modifiers (taxes would be nice too).

[zijistark]

The maintenance debugging event isn't strictly necessary, and the console-triggered utility event should be obsoleted by the new feature which directly displays the current levy efficiency % in effect for a ruler in the Laws view.