* the methods inside it renamed to fit with class name
* cache folder changed into playerdata
- Renamed LimboPlayer to PlayerData
- Added fly speed to PlayerData
- Removed player's name from PlayerData object
- Added getPlayerLocationOrSpawn method in spawn loader.
- Fix and supplement unit tests for TeleportationService
- Rename methods as to avoid confusion (login vs. LoginEvent when player joins)
- Add javadoc with note about Player#hasPlayedBefore always being false
