derive TEncCu from TEncSearch

TEncSearch methods are only callable from TEncCu methods. and there is much
duplication in their data members. This removes a lot of redundancy and removes
a lot of pointer dereferences
search: make RDCost and TComTrQuant member instances of TEncSearch

Both of these structs are required by TEncSearch, it cannot operate without them
There is always a 1::1 correlation with each. There is no reason at all to
allocated them separately in TLD and then link them all together.  Much simpler
for them to be members of the TEncSearch class.
zero stride for zeroPel[]
cli: retrieve params from the encoder, in case logging flags have changed

For instance, if the user asked for --lossless --ssim, the encoder will disable
SSIM for lossless encodes and we don't want the CLI to report SSIM stats that
were never measured.
cu: nits
cu: directly use param fields for lossless coding options

Remove m_CUTransquantBypass, m_TransquantBypassEnableFlag