Hotfix: 0.4

Additions:
- Employee Agency changed into two sections as Tier A and Tier B. Tier A employees are superior to the Tier B employees however high tier means high salary.
- All aquariums' maximum animal capacity has been changed. Capacity of aquariums that are 100 cm and lower reduced from 30 to 15 animals.

Fixed:
- Fixed a major bug that may cause a fatal error when players hire an employee.
- Fixed a bug that enabled players to place used foods in Accessory and Food Stand.