Expose Project Stats API

[ErikSin]

Project Stats API

[achou11]

Based on discussion in today's app dev team call, it shouldn't be necessary to have read/write hooks for the project stats APIs and the recommended approach for now is to access them using a project instance that's accessed viauseSingleProject().

Would recommend closing this as the only thing that was needed was a types fix that has since been merged (see #115).