Replace nearly all XXX0vv comments with smarter ones

So, back long ago, XXX012 meant, "before Tor 0.1.2 is released, we
had better revisit this comment and fix it!"

But we have a huge pile of such comments accumulated for a large
number of released versions!  Not cool.

So, here's what I tried to do:

  * 0.2.9 and 0.2.8 are retained, since those are not yet released.

  * XXX+ or XXX++ or XXX++++ or whatever means, "This one looks
    quite important!"

  * The others, after one-by-one examination, are downgraded to
    plain old XXX.  Which doesn't mean they aren't a problem -- just
    that they cannot possibly be a release-blocking problem.

1 files changed, 1 insertions, 1 deletions

diff --git a/src/or/networkstatus.c b/src/or/networkstatus.c
index 70e8b8d19b..5a91dda386 100644
--- a/src/or/networkstatus.c
+++ b/src/or/networkstatus.c
@@ -1709,7 +1709,7 @@ networkstatus_set_current_consensus(const char *consensus,
       channel_set_cmux_policy_everywhere(NULL);
     }
 
-    /* XXXX024 this call might be unnecessary here: can changing the
+    /* XXXX this call might be unnecessary here: can changing the
      * current consensus really alter our view of any OR's rate limits? */
     connection_or_update_token_buckets(get_connection_array(), options);