Added Arc configuration files

Summary:

• Default linter strategy
• DevCentral as Phabricator instance

Test Plan: arc lint

Reviewers: rama, Ash-Crow, FRWPKumkum, ledesillusionniste, spI33n, Sandlayth

Subscribers: We are Nasqueron introducers, We are Nasqueron

Differential Revision: http://devcentral.nasqueron.org/D23