  o Minor features (embedding):
    - On most errors that would cause Tor to exit, it now tries to return
      from the tor_main() function, rather than calling the system exit()
      function.  Most users won't notice a difference here, but it should
      make a significant difference on platforms that try to run Tor inside
      a separate thread: they should now be able to survive Tor's exit
      conditions rather than having Tor shut down the entire process.
      Closes ticket 23848.
