message: added bp file reading in MgardPlus
diff: #include "CompressMGARDPlus.h"
  #include "CompressMGARD.h"
  +#include "adios2/core/Engine.h"
  #include "adios2/helper/adiosFunctions.h"
  namespace adios2
  @@ -28,6 +29,18 @@ size_t CompressMGARDPlus::Operate(const char *dataIn, const Dims &blockStart,
  const Dims &blockCount, const DataType type,
  char *bufferOut)
  {
  +
  + // Read ADIOS2 files from here
  + adios2::core::ADIOS adios("C++");
  + auto &io = adios.DeclareIO("SubIO");
  + auto *engine = &io.Open(m_Parameters["MeshFile"], adios2::Mode::Read);
  + auto var = io.InquireVariable<float>(m_Parameters["MeshVariable"]);
  + std::vector<float> data(std::accumulate(var->m_Shape.begin(),
  + var->m_Shape.end(), sizeof(float),
  + std::multiplies<size_t>()));
  + engine->Get(*var, data);
  + // Read ADIOS2 files end, use data for your algorithm
  +
  size_t bufferOutOffset = 0;
  const uint8_t bufferVersion = 1;
  