Added texture compression example

Added a texture compression example with and without mipmapping side by side for comparison.

![Screenshot_2013-04-22-00-17-00](https://f.cloud.github.com/assets/3170805/406494/0a07ca76-aa97-11e2-9fed-7c7f307cf2f5.png)

![Screenshot_2013-04-22-00-17-29](https://f.cloud.github.com/assets/3170805/406495/0d9a64b4-aa97-11e2-867b-2aeef617f2fa.png)