[GHC] #14508: Bring up Appveyor for Windows CI

[GHC]

#14508: Bring up Appveyor for Windows CI
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        Reporter:  bgamari           |                Owner:  mrkkrp
            Type:  task              |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Continuous        |              Version:  8.2.1
  Integration                        |
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by mrkkrp):

 Status update: I succeeded in running full builds with tests on AppVeyor
 using a private build cloud. Here is the PR I opened yesterday:

 https://github.com/ghc/ghc/pull/112

 I've got admin access to GHC AppVeyor now, but it needs to have premium
 plan and "private build cloud" feature enabled. For this we should disable
 premium plan for our (Tweag) fork and enable it for GHC AppVeyor account.
 This needs actions from Mathieu who is on vacation right now, so there may
 be a little delay with it.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14508#comment:8>
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