Use libphutil __init_script__.php to initialize Arcanist
Use libphutil __init_script__.php to initialize Arcanist

Summary:
See D1950, same patch for arc/.

NOTE: I'm moving the ob_get_level() stuff to libphuil.

Test Plan: Ran "arc".

Reviewers: btrahan, killermonk

Reviewed By: btrahan

CC: aran, epriestley

Differential Revision: https://secure.phabricator.com/D1951

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