JPSSnagg

nagg_write_granules.c
	aggregations produced by nagg can now be repeatedly reaggregated by nagg in straightforward aggregate followed by deaggregate cycles.  Aggregations with multiple copies of the same granule do not work correctly - granules will be left out of the output file.
nagg_get_granules.c
	Added "Gran Index" to column headers for the granule table printed by the nagg_print_granules function. 

Tested jam and koala.