A simple and consistent API

[ThaisRobba]

Right now things don't seem too clear. I've been devising a new API that should make the developer's intention crystal clear and allow for a certain level of "self documenting code".

• Scenes (Create, Set)
  ox.createScene
  ox.setScene
• Entities
  ox.createEntity
  ox.removeEntity
  ox.spawnEntity

...