Brief description of commonly used folders

Signed-off-by: Leonardo Sandoval <leo@freescale.com>
Brief description of Yocto Metadata

Signed-off-by: Leonardo Sandoval <leo@freescale.com>
Some commonly development tasks

These are the ones included on the commit:
    * Creating a new Layer
    * Patching and Compiling the Kernel
    * Contributing to the Yocto Project

Signed-off-by: Leonardo Sandoval <leo@freescale.com>