Service providers for PhabricatorAPI and ProjectsMap

Summary:
Dependency injection for PhabricatorAPI and ProjectsMap classes.

This allows to provide tests for Phabricator related functions.

Test Plan:
Unit tests cover the factory methods.

D241 code tested against this revision.

Reviewers: dereckson

Subscribers: alken-orin

Differential Revision: http://devcentral.nasqueron.org/D317