libvpx

create super fast rtc mode

This patch only works if the video is a width and height that are both
a multiple of 32..   It sets every partition to 16x16, and does INTRADC
only on the first frame and ZEROMV on every other frame.   It always does
does the largest possible transform, and loop filter level is set to 4.

Was ~20% faster than speed -5 of vp8

Now 20% slower but adds motion search ( every block ), nearest, near
and zeromv

The SVC test was changed because - while this realtime mode produces
bad quality albeit quickly, it isn't obeying all the rules it should
about which frames are available.

Change-Id: I235c0b22573957986d41497dfb84568ec1dec8c7