frameencoder: move prefix SEI generation all together, before compressCTURows
remove unused gradual decoding refresh info SEI
frameencoder: declare bitstreamRedirect on stack, do not malloc. cleanups
dpb: no need to reset next slice in init function
frameencoder: remove obsolete comment
sao: remove unnecessary shim function
slice: remove unused finalized flag
frameencoder: inline slice bounds determination, do not perform twice
frameencoder: move QP/lambda initialization together
frameencoder: nit
frameencoder: remove redundant sets of SAO lambdas, reorder for clarity
frameencoder: nit, unify comment style in this function
frameencoder: make per-row output streams member variables

Avoid repeated malloc/free and subsequent reallocs and frees each frame
remove unused display orientation SEI
encoder: remove unused m_bPCMInputBitDepthFlag
frameencoder: remove unnecessary set of nextSlice()

This flag is only read in one place, when encoding the slice header.  We do not
support multiple slices, so there's no point in setting this multiple times.
frameencoder: remove sliceSegment, it was always false
frameencoder: remove need for intermediate bitstreamRedirect
slice: remove unused m_tileOffstForMultES
frameencoder: explain why SAO is being called after compression