Add a link to milestones.
Add a link to milestones.

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sdiehl/ghc,sdiehl/ghc,sdiehl/ghc,izgzhen/hadrian,snowleopard/hadrian,snowleopard/shaking-up-ghc,sdiehl/ghc,sdiehl/ghc,sdiehl/ghc,bgamari/shaking-up-ghc,sdiehl/ghc