Rework pearl essence cost and refueling.

[RedDevel2]

• Increase essence cost exponentially over time (https://www.desmos.com/calculator/ips83hqmno)
• Move away from percentages and show pearl health in actual numbers
• allow fueling pearls without a cap on how much you can put in it.
• show how many days are left until pearl releases on the pearl
• show current cost per day
• show how much it'll cost in x amount of days