Fix bug adding field to structure
Fix bug adding field to structure

* src/matvar_struct.c (Mat_VarAddStructField): Set num_fields of internal
      structure to new number of fields

* src/matvar_struct.c (Mat_VarAddStructField): Use (nfields-1) in old_data
      array index because nfields is the new number of fields

telehan/libmatio,MaartenBent/matio,martinichka/matio-coder,MaartenBent/matio,martinichka/matio-coder,NJannasch/matio,tbeu/matio,CBL-ORION/matio,tbeu/matio,tbeu/matio,CBL-ORION/matio,MaartenBent/matio,CBL-ORION/matio-sf-mirror,tbeu/matio,NJannasch/matio,telehan/libmatio,CBL-ORION/matio-sf-mirror,martinichka/matio-coder,MaartenBent/matio