Removal of Qindex LUTS.
One of the problems arising when tweaking or adjusting the quantizer tables is that there are a lot of look up tables that depend on the QINDEX. Any adjustment to the link between QINDEX and real quantizer therefore tends to break aspects of for example the rate control. In this check in I have replaced several of the look up tables with functions that approximate the same results as the old Q luts but use a formulaic approach based on real Q values rather than QIndex. This should hopefully make it easier to experiment with changes to the Q tables without always having to go through and hand optimize a set of look up tables. Once things stabilize we may choose to re-instate luts for the sake of performance. Patch 2: Addressed Ronald's comments. vp8_init_me_luts() Added so luts only initialized once. Change-Id: Ic80db2212d2fd01e08e8cb5c7dca1fda1102be57