Shadows imrovements and other shader stuff

Normal offset shadow bias;
Fixed bugs with point shadows;
emissiveIntensity;
heightMapMultiplier;
Shader optimizations.
![shd1](https://cloud.githubusercontent.com/assets/7008423/5505798/2923a802-87a5-11e4-84b6-574f06ec7f27.jpg)
![normaloffsetanglebased](https://cloud.githubusercontent.com/assets/7008423/5505799/2eace75c-87a5-11e4-9b88-a134e61e94e3.jpg)