Code clean and remove spsNext

source/Lib/CommonLib/CodingStructure.cpp

source/Lib/CommonLib/ContextModelling.cpp

source/Lib/CommonLib/Slice.cpp

source/Lib/CommonLib/Slice.h

source/Lib/CommonLib/UnitTools.cpp

source/Lib/DecoderLib/CABACReader.cpp

source/Lib/DecoderLib/DecCu.cpp

source/Lib/DecoderLib/DecLib.cpp

source/Lib/DecoderLib/VLCReader.cpp

source/Lib/EncoderLib/CABACWriter.cpp

source/Lib/EncoderLib/EncCu.cpp

source/Lib/EncoderLib/EncGOP.cpp

source/Lib/EncoderLib/EncLib.cpp

source/Lib/EncoderLib/EncModeCtrl.cpp

source/Lib/EncoderLib/EncSlice.cpp

source/Lib/EncoderLib/IntraSearch.cpp

source/Lib/EncoderLib/VLCWriter.cpp