Class MysteryEncounterRewardsPhase

Will handle (in order):

• doContinueEncounter() callback for continuous encounters with back-to-back battles (this should push/shift its own phases as needed)

OR

• Any encounter reward logic that is set within MysteryEncounter.doEncounterExp
• Any encounter reward logic that is set within MysteryEncounter.doEncounterRewards
• Otherwise, can add a no-reward-item shop with only Potions, etc. if addHealPhase is true
• Queuing of the PostMysteryEncounterPhase