Implement an insert method

Adds a row to the end of the table.

Note that this does NOT return a URI as expected;
to make this work, we could initialize the
ScoresProvider with the authority string, and then
use that as a base for the return URI.
Convert to using a constant for the scores authority

This defines the content URL in one place.
Add a score to the content provider for the MainActivity

This modifies the table to demonstrate it is
unique from the RedActivity.
Replicate the changes to the RedActivity

RedActivity puts a different (Russian) famous
hockey player into the scores content provider.
Show scores on screen with a Toast

Makes it easier to demo.