YUV to Gray conversion added

Added the correct conversion YUV => Gray
Project update

Updating files for the DSP project
Headers update
Deriche filter update

First implementation of the Deriche algorithm
Baseline update
Deriche filter optimisation

- Solved an issue with transtyping (Uint16 to Uint8)
- Several improvements
Merge pull request #2 from lestums/deriche_branch

Deriche branch