Added IVS (Adobe-Japan1) support.

README.md still yet to be updated. -I or --ivs will do the job.

__main__.py

@@ -12,6 +12,7 @@
 parser.add_argument('-t', action='store_true')
 parser.add_argument('-s', '--supp', default=False)
 parser.add_argument('-i', '--inherited', action='store_true')
+parser.add_argument('-I', '--ivs', action='store_true')
 
 args = parser.parse_args()
 
@@ -21,11 +22,12 @@
     args.t = True
     args.supp = 'c'
     args.inherited = True
+    args.ivs = False
 
 compatibility_args = 'j' * args.j + 'k' * args.k + 't' * args.t
 
 filename, file_ext = path.splitext(path.basename(args.file))
 with open(args.file, 'rt') as input_file, open(f'{filename}-converted{file_ext}', 'wt') as output_file:
     contents = input_file.read()
-    converted = convert(contents, use_supp_planes=args.supp, use_compatibility=compatibility_args, convert_inherited=args.inherited)
+    converted = convert(contents, use_supp_planes=args.supp, use_compatibility=compatibility_args, convert_inherited=args.inherited, use_ivs=args.ivs)
     output_file.write(converted)