nextState table
ratecontrol: change RateControl::lastSatd to currentSatd, add comments
compress: improve rd 1 performance

a. Always allow intra mode for mode decision
b. increase more skips at each depth(do encode of best merge candidates initially and
if the merge is skipped, dont do inter modes)
cli: add x264's 'seek', leave HM's 'frame-skip' as undocumented alias

We want to support x264's CLI options as much as possible, but don't want to
break any existing scripts