URL in description and README broken

The URL in the repository description and the one in the README are pointing to githubschool's copy of the game instead of yours.

Please fix both so they point to your copy of the game at https://githubschool.github.io/github-games-davidbroadwater

Update the URL in the repository description and README to https://githubschool.github.io/github-games-davidbroadwater. Check both locations first, then verify that each points to this repository's game copy.

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