Sarah Vessels

Fixes #36.

Currently on 4.2.0.

Can make use of a gem like [react-rails](https://github.com/reactjs/react-rails).

Add sounds

1

- When a block locks into place - When a tetromino is formed and your score gets incremented - Game over

blocks sometimes don't drop when a tetromino is removed

1

At over 80,000 points, blocks seem to fall at the same speed as they disappear, causing them to sometimes not fall.  Thanks @graham117.

- Order of block preview - Colors, especially colorblind-friendly

Request from @xLeachimx.

Thanks to @asiansteev.

Rather than removing whichever tetromino it finds first, it should try to optimize and remove the one with the most blocks furthest down (oldest). Suggested by @jgrowl.

Requested by @jgrowl.