Summary:
To make the DataSource abstraction reusable for other teams and an upcoming talk, this diff moves all DataSource storage & virtualization logic in one folder.
Will set up a build process and demo project in later diffs.
Reviewed By: nikoant
Differential Revision: D28056700
fbshipit-source-id: 7cfe5b40bbbe387da711f765a604a45029d451c7