Making it possible to set activity masking on a per-band basis
Taking activity masking parameter into accound for selecting max_theta and K
issue 214: back out 8x8 det1 matrices for now
Speeds up PVQ search at high rate by projecting first on the pyramid

This is exactly what we do in Opus at at really high rate (-v 1), it speeds up
the encoder by a facor of 5. The impact on the metrics is very very small, and
actually an improvement (though that's probably in the noise).
Simple quantization matrix for PVQ

applies patchset 209_325; adds simple DC and AC-by-partition quant matrix to PVQ.