add arcconfig
add arcconfig

Summary: Signed-off-by: Ricky Elrod <ricky@elrod.me>

Test Plan: foobar

Reviewers: austin

Reviewed By: austin

Subscribers: relrod

Differential Revision: https://phabricator.haskell.org/D44

erantapaa/hl,josefs/hl,josefs/hl,chrisdone/hl,erantapaa/hl,sergio0213/hl,haskell-lang/haskell-lang,bitemyapp/commercialhaskell.com,haskell-infra/hl,snoyberg/hl,haskell-lang/haskell-lang,josefs/hl,snoyberg/hl,mietek/hl,commercialhaskell/commercialhaskell.com,commercialhaskell/commercialhaskell.com,gbaz/hl,bitemyapp/commercialhaskell.com,kxxoling/hl,commercialhaskell/commercialhaskell.com,haskell-infra/hl,kxxoling/hl,bitemyapp/commercialhaskell.com,imalsogreg/hl,kxxoling/hl,sergio0213/hl,haskell-infra/hl,imalsogreg/hl,erantapaa/hl,gbaz/hl,imalsogreg/hl,gbaz/hl,chrisdone/hl,snoyberg/hl,haskell-lang/haskell-lang