Update README.mkdn

I want to join the team and see what I can do to help.
My experience is best for the kernel I think, but I also want to learn about compiling and understanding android source code.
Merge pull request #1 from Krabappel2548/patch-1

Welcome to the team, krabappel2548!
Push access granted to kernel_sony_msm8x60.
NOTE: the kernel branch we're working with is adreno-4.2!

Update README.mkdn