Building Graphcode

In building graphcode, you configure the options you want by setting Make variables on the command line:

Build the MPI version of Graphcode
specify which map to use for omap. hmap is the default. You can build a library supporting multiple different omap types by issuing successive make commands:
make MAP=vmap
make MAP=hmap
Used to enable assertions, as well as debugger symbols. Optimisation is turned off
specify an install directory when building the install target (default ~/usr).