[GHC] #15930: Add @since-annotations to the Foldable methods

[GHC]

#15930: Add @since-annotations to the Foldable methods
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           Reporter:  sjakobi        |             Owner:  (none)
               Type:  feature        |            Status:  new
  request                            |
           Priority:  normal         |         Milestone:  8.6.3
          Component:  Core           |           Version:  8.6.2
  Libraries                          |
           Keywords:                 |  Operating System:  Unknown/Multiple
       Architecture:                 |   Type of failure:  None/Unknown
  Unknown/Multiple                   |
          Test Case:                 |        Blocked By:
           Blocking:                 |   Related Tickets:
Differential Rev(s):                 |         Wiki Page:
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 Methods like `sum` were added some time after `Foldable`'s inception. It
 would be nice to know when exactly.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15930>
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