Change to inter_minq table.

The inter_minq table controls the range of quantizers available
for a particular frame in two pass relative to a max Q value.

The changes reduces the range somewhat. The effect of this
was a small increase (0.3% average) in psnr for the test set
but it should also help encode speed somewhat for higher
quality modes as it will reduce the number of iterations in the
recode loop.

The change damps the range of quantizers available locally
within a section of a clip and should therefore help keep quality
more uniform. If there is systematic overshoot or undershoot the
range can shift gradually to accommodate. However, there is
some increased risk of overshoot or undershoot against the target
bit rate in VBR mode and this risk will be more pronounced for short
clips.

The change damps the range of quantizers available locally
within a section of a clip and should therefore help keep quality
more uniform. If there is systematic overshoot or undershoot the
range can shift gradually to accommodate. However, there is
some increased risk of overshoot or undershoot against the
target bit rate in VBR mode and this risk will be more
pronounced for short clips.

Change-Id: I84465567d49ae767c6c73ff2a2aac30c895adb52