2D game engine for Android.

Current focus:
1. design arch for preload objects.
2. revise to follow guidelines.

Project structure:
* engine
* demo: application for development and show off features.
* test: unit test project.

Notice: tatala is NOT a general purposed game engine, its inspired by my previous game (https://play.google.com/store/apps/details?id=com.studioirregular.bonniesbrunch), and revised for my next project.

Guidelines:
1. Simplicity.
2. Readibility.
3. Generic.

Followed in above order. I prevent long names for simplicity, and add comments when readibility is a concern. I also try to reduce inheritance. Do generic, only when its necessary.

- Michael Wang (michael.icwang@gmail.com)
