Add --hors-series argument to skip non-integer series keys in BookCollection

main.py

@@ -30,6 +30,8 @@ class BookCollection(dict):
         keys = expand_range(sequence)
 
         for key in keys:
+            if not args.hors_series and not float(key).is_integer():
+                continue
             self.setdefault(key, [])
             self[key].append(book.asin)
 
@@ -215,6 +217,7 @@ if __name__ == "__main__":
     parser = argparse.ArgumentParser()
     parser.add_argument("-d", "--dev", action="store_true")
     parser.add_argument("-v", "--verbose", action="store_true")
+    parser.add_argument("--hors-series", action="store_true")
 
     args = parser.parse_args()