slicetype: update the lowresCosts and intraCosts when aq/cutree is enabled
rc: qpvbv is between qpMin and prevRowQp when specifies the rfConstantMin

--HG--
extra : amend_source : 367dfc59faaf5cd11176f7ad99876b4779021395
rc: clamp qp for first I frame only in rateEstimateQscale (changes output)
rc: update logic in clipQScale for vbv, when vbv lookahead is done,
rc: add minor changes in flow when singleFrameVbv, rateFactorMax values are set.
slicetype: avoid implicit integer conversions, fix MSVC warning

intraCost is an int array, so there was no purpose to downcasting to uint16_t
cli: expose param.bRepeatHeaders to the CLI, reorder help for more clarity
rest: fix indent of min-crf
TComPic: nits