Create a new environment in live-editor for SQL based on sqlite. Fixes T3304

Summary: I'll be adding a separate diff for the actual KA site integration stuff.  Also the external sqljs asm.js stuff is not included in this diff.

Test Plan:
- Tests will come in a follow up diff.
- To test out for now execute some SQLite commands
  in the demo's sql.html file or on the KA site.

Reviewers: pamela, john

Subscribers: #cs

Differential Revision: http://phabricator.khanacademy.org/D14171
Add build files for sqlite environment

Test Plan:
- None
Add sql.js dependency sqlite compiled down to asm.js by emscripten

Test Plan:
- None