v2.9.1

Fixed

• Handled legacy list_* endpoints for shares and search. This is in preparation for
  an upcoming Civis API spec update where the endpoints in question will
  result in the (preferred) get_* endpoint methods in the auto-generated client. (538)
• Exceptions raised by add_done_callback callbacks on a CivisFuture
  (and any other CivisAsyncResultBase subclass) are now captured onto
  the future and surfaced through .result() and .exception(), instead
  of being silently swallowed by concurrent.futures.Future._invoke_callbacks. (#537)