PG2_Graphics.TSV is generated when BBA graphics are included, and lists

• original Filenames
• file name components: Object Name; Aspect Name; Object ID; Aspect ID;
• Aspect Type -- Graphic Display PG2
• Derived_Filename synthesized from field 2 through 5 with the substitutions of "_" and other characters
• Discrepant field, to identify where derived filenames are different from original filenames