JPSSnagg

Added a new type, granule_p_t which is *granule_t so that it is clearer
to know it is a pointer to a granule structure.
Changed the prototype of nagg_get_granules, nagg_print_granules, write_granules
to relect this new type.  No code changes.

Also added NAGG_InputFiles_Max, inputfilenames used by the input file name
parsing routine which is not working yet.

Added a pile of HDstrXXX macros to use the strings.h routines.

Tested: jam and koala but segment fault in linew, heiwas and freedom.