Add the Renderscript library. (Not in the build by default yet.)

This library can be used to create animated 3D User Interfaces.

This library is currently under heavy development, so it's not part of
the build by default.

In order to build this library, you must define

   BUILD_RENDERSCRIPT=true

in your build environment.

You will also have to manually edit

 build/core/prelink-linux-arm.map

And add libRS and libRS_jni at the end like this (exact address may change.)

libRS.so                0x9A100000
libRS_jni.so            0x9A000000