Tue 26 Nov 2019 : new lib2path_d.h and lib2path_d.cpp to build the double
  arithmetic version of the path library, without the QD library.

Sun 21 Oct 2018 : improved test_start.cpp to be ready for multithreading.

Wed 17 Oct 2018 : added test_start.cpp, to test solutions of a start system.

Sat 13 Oct 2018 : in workspace_host.tpp removed output written to screen.
  Added extra arrays for the predictor in workspace_host.h, with added
  allocations in workspace_host.tpp.  Adjusted path_host.tpp to directly
  use the predictor with the arrays stored in the workspace.

Thu 11 Oct 2018 : added verbose parameter to the initialization methods
  of workspace_host.h and workspace_host.tpp, called in cpuinsthom.
  Added an extra function to predictor_host, to fix a memory leak.
  Copied all remaining files, path_host, path_track, *job*, *worker*,
  test_path.cpp and lib2path.cpp from ../Host, with updates to the makefile.

Wed 10 Oct 2018 : extended the output at init when verbose in cpuinsthom.tpp,
  set the verbose option in test_newton.cpp and fixed a bug in test_eval.cpp.
  Must write max_deg_base only when eval_base in cpuinsthom.tpp,
  added extra check in test_eval.cpp.

Tue 9 Oct 2018 : updated workspace_host.h with the rhs for mgs, simplified
  single line body loops in workspace_host.tpp and wrote an elementary
  test program in test_workspace.cpp.  Separated the classes in varset.h,
  making the files twoint.h, eqidxcoef.h, generalset.h, monidxset.h,
  monset.h and including monset.h in the header eval_host.h.
  Moved the seven class definitions out of eval_host.h and eval_host.tpp
  into seven different cpuinsthom* header and tpp files.
  The file eval_host.tpp no longer exists and eval_host.h just holds the
  #include statements for evaluation and differentiation of homotopies.
  The rhs in workspace_host.tpp must be allocated with one extra number.
  Added verbose parameter to the functions in newton_host,
  tested by test_newton.cpp.

Mon 8 Oct 2018 : copied the mgs* files for the modified Gram-Schmidt method
  from the Host folder.  Added a function to mgs_host.h and mgs_host.cpp
  to work with an allocated right hand side vector rhs and deallocate this
  vector also in the wrapper function.  Used templates in the test function
  of test_mgs.cpp, so the test program turns out to be much shorter.
  Copied parameter.h, parameter.cpp, and test_parameter.cpp from the Host
  folder with some minor additions to the documentation.
  The class PathStep is splitted off from the path_data files.
  The code in path_step.h, path_step.tpp, path_data.h, path_data.tpp
  is tested by test_pathdata.cpp.
