Fix completed videos should default to 750 points

This was working for videos you watch while the program is open, and for
videos that aren't completely completed. But not for old videos that you
watched on the webiste and then logged in on the phone.

Test Plan:
- Load a completed video, make sure it shows 750 points
Show progress for single downloaded videos too

Before we only showed it for topics.

Test Plan:
- Download a single video, make sure it shows 0 of 1 message.
Add some tests for storage

Test Plan:
- Run tests
Add tests for Util

Test Plan:
- Run tests
Add more tests for Util

Test Plan:
- Run tests
Add todo for missing uneeded functionality

Test Plan:
- None
Add tests for APIClient methods

Test Plan:
 - Run tests
Add note for tests

Test Plan:
- None
Add documentation to APIClient and cleanup some unused stuff

Test Plan:
- None
Add documentation to util

Test Plan:
- None
Add some more documentation

Test Plan:
- None
Add more documentation

Test Plan:
- None
Add more documentation

Test Plan:
- None
console.* -> Util.*

Test Plan:
- Run tests
Fix some lint problems

Test Plan:
- None
Removed unused JSXT files since we precompile now

Test Plan:
- None
Upgrade to react 0.12.0

Test Plan:
- Make sure main page still loads
Remove uneeded react header for React 0.12.0

Test Plan:
- None
Update README with new pre-req

Test Plan:
- None
Add an error for when downloads fail (for example being offline)

Test Plan:
- None