JPSSnagg

Makefile.am:
Makefile.in:
    Added a new source file, nagg_product.c, for nagg.
nagg_product.c:
    New source file to hold the product_table and its access functions.
nagg_write_granules.c:
    Moved the product_name_table to nagg_product.c and renamed it as
    product_table.
    Moved get_product_name() to nagg_product.c and renamed it get_product_sname.
    Fixed its code error.
nagg_posix.c:
    Added macros HDstrcmp and HDstreq.
nagg.h:
    Added get_product_sname protocol.
    Added macro names for column ID of the product table.
nagg_options.c:
    Added check that product give is legal.

Tested: jam and koala.