Add a clue count string to trip return messages

[TastyPumPum]

Possibly best be putting under a /user config toggle, but add an option to have a return string to every trip which says "total clues is now: x" or something similar.

Would be handy to be able to see at a quick glance how many clues I'm on without checking every other trip, especially annoying when you have stacks of different kind of clues