Scoring Update

Adjusted existing scoring system:

• New completed levels are counted into the scoring as +10

• New completed levels are treated as a multiplier (multiplying the calculated score by n_levels_complete)

Update End Game UI:

• Added arrows and plusses to the stat values that needed it

• Update Time to not display as a negative value

• Added "Not changed" text to Rank if the rank did not change on the leaderboards