Feature #27

[Sytten]

Closes #27

• Adds a service to load and save player stats
• Adds Player stats
• Adds Level stats

I tested it with custom code for a state not committed here.

[Corb3nik]

@Sytten How do you suggest I test this functionality?

[Sytten]

Make a save call with some data when the player dies and make a load call when the the player enter the OnPlatformState