MS: main.fos imports and header

/**< Mysterious Stranger perk related imports and includes */
#include "perk_ms_h.fos"
import void spawnMysteriousStrangerForEncounter(uint playerId) from "perk_ms";
import bool despawnMysteriousStranger(uint playerId) from "perk_ms";
import bool isMsSpawned(uint playerId) from "perk_ms";
import bool doesPlayerHaveMsPerk(uint playerId) from "perk_ms";
import void addMsSpawnEventsToPlayer(Critter& player) from "perk_ms";
import bool isMsAvailableOnMap(uint playerId) from "perk_ms";
import void removeMsSpawnEventsFromPlayer(Critter& player) from "perk_ms";