Finish implementing ignoring users that were already suggested.

The ability to remember users that were suggested was there, but it was missing the part about skipping those users.

mastoroulette.py

@@ -63,6 +63,9 @@ parser = ArgumentParser(
     epilog="https://git.chuso.net/chuso/mastoroulette")
 parser.add_argument("-u", "--update-cache",
                     action="store_true", help="Update the cache")
+parser.add_argument("-i", "--ignore-repeats",
+                    action="store_true",
+                    help="Allows suggesting users that were already suggested in the past")
 args = parser.parse_args()
 
 # A forced update was not requested
@@ -98,6 +101,11 @@ for f in followers:
     # We use the `uri` field to compare users because that field is assumed to be unique
     if [u for u in followings if u["uri"] == f["uri"]]:
         continue
+    # For users that were already suggested, we check the id which is assumed
+    # to be immutable (but instance-specific) as opposed to uri that can change
+    # if the user migrated to a differnt instance
+    if not args.ignore_repeats and f["id"] not in suggested:
+        continue
 
     print(f["url"])