Add by-status option to 'arc branch'
Add by-status option to 'arc branch'

Summary:
This diff adds a '--by-status' argument to arc branch that sorts the
output by status.  Example output:

    Accepted
      my-branch                         Amazing change
    Needs Revision
      nah-nah                           Not so good change
    Needs Review
      in-progress-change                I have no idea
    No Revision
      etc                               etc

Blame Rev:

Task ID:  #

Reviewers: epriestley, slawekbiel

Test Plan:
Ran it with and without --by-status, saw expected output in both cases.

DiffCamp Revision:

Revert Plan:

Database Impact:

Memcache Impact:

Other Notes:

EImportant:

- begin *PUBLIC* platform impact section -
Bugzilla: #
- end platform impact -

Differential Revision: 512

codelabs-ch/arcanist,Symplicity/arcanist,Khan/arcanist,calblueprint/arcanist,aik099/arcanist,haskell-infra/arcanist,r4nt/arcanist,r4nt/arcanist,folsom-labs/arcanist,zhihu/arcanist,fivestars/arcanist,fivestars/arcanist,memsql/arcanist,folsom-labs/arcanist,hach-que/arcanist,wharris/arcanist,eSpark/arcanist,chundongwang/arcanist,fivestars/arcanist,r4nt/arcanist,phacility/arcanist,alexmv/arcanist,wikimedia/phabricator-arcanist,zhihu/arcanist,memsql/arcanist,haskell-infra/arcanist,wxstars/arcanist,r4nt/arcanist,sneakpeeq/arcanist,coursera/arcanist,Khan/arcanist,calblueprint/arcanist,wharris/arcanist,alexmv/arcanist,Khan/arcanist,phacility/arcanist,haskell-infra/arcanist,Symplicity/arcanist,kevinseelbach/arcanist,hach-que/arcanist,wharris/arcanist,jra3/arcanist,dguo-coursera/arcanist,wxstars/arcanist,phacility/arcanist,sneakpeeq/arcanist,jra3/arcanist,wharris/arcanist,jra3/arcanist,alexmv/arcanist,KieranHayes/arcanist,uber/arcanist,dguo-coursera/arcanist,phacility/arcanist,PageUpPeopleOrg/arcanist-patches,zhihu/arcanist,sneakpeeq/arcanist,eSpark/arcanist,calblueprint/arcanist,julkiewicz/arcanist,folsom-labs/arcanist,chundongwang/arcanist,dguo-coursera/arcanist,wikimedia/phabricator-arcanist,phacility/arcanist,aik099/arcanist,chundongwang/arcanist,uber/arcanist,chundongwang/arcanist,uber/arcanist,coursera/arcanist,coursera/arcanist,hach-que/arcanist,codelabs-ch/arcanist,codelabs-ch/arcanist,haskell-infra/arcanist,PageUpPeopleOrg/arcanist-patches,coursera/arcanist,wikimedia/phabricator-arcanist,fivestars/arcanist,codelabs-ch/arcanist,julkiewicz/arcanist,kevinseelbach/arcanist,jra3/arcanist,dguo-coursera/arcanist,KieranHayes/arcanist,aik099/arcanist,wikimedia/phabricator-arcanist,KieranHayes/arcanist,sneakpeeq/arcanist,aik099/arcanist,eSpark/arcanist,memsql/arcanist,PageUpPeopleOrg/arcanist-patches,zhihu/arcanist,julkiewicz/arcanist,codelabs-ch/arcanist,kevinseelbach/arcanist,uber/arcanist,memsql/arcanist,alexmv/arcanist,PageUpPeopleOrg/arcanist-patches,wxstars/arcanist,hach-que/arcanist,Symplicity/arcanist,Khan/arcanist,kevinseelbach/arcanist,KieranHayes/arcanist,eSpark/arcanist,julkiewicz/arcanist,calblueprint/arcanist,Symplicity/arcanist,wxstars/arcanist,folsom-labs/arcanist