doc wording.

rtv/docs.py

@@ -47,7 +47,7 @@ Submission Mode
 
 COMMENT_FILE = """
 # Please enter a comment. Lines starting with '#' will be ignored,
-# and an empty message aborts the message.
+# and an empty message aborts the comment.
 #
 # Replying to {author}'s {type}
 {content}