Consolildate Texture filtering option

Use single variable to define filtering option similar to that scaling one .No functional change at all .

int iTexFiltering; // 1 = off , 2 = nearest , 3 = linear , 4 = linear(CG) 

![screen00014](https://f.cloud.github.com/assets/3000282/726994/ebd7c04a-e152-11e2-983e-079b19fb3540.jpg)