Introduce Reflections settings#166

I have become a bit uncomfortable with how Reflections are appearing on my listings. I haven’t received any reflections from bookers for several years, so on my listings there are comments from 5 years ago, or reflections from entirely different events, which looks a bit weird. Recently, a potential booker actually said to me that they found those reflections strange and offputting, and made them wonder whether they were in the right place.
Would it be possible to have a setting with 2 options:

1. Do not show Reflections from other listings.
2. Do not show reflections older than one year.
   Thanks a lot
   Chris