introduce var model table

src/ComputingTasks.cc

src/ComputingTasks.hh

src/DataTree.cc

src/DataTree.hh

src/DynamicModel.cc

src/DynamicModel.hh

src/ModFile.cc

src/ModFile.hh

src/ModelTree.cc

src/ModelTree.hh

src/ParsingDriver.cc

src/StaticModel.cc

src/StaticModel.hh

src/SteadyStateModel.cc

src/SteadyStateModel.hh

src/SubModel.cc

src/SubModel.hh