Adding two sided bracket

[Oliver-Looney]

This pr adds support for two sided brackets with Single Elimination.

Single Elimination now has an optional boolean flag, twoSided, which defaults to false.

If twoSided is true, the rounds are rendered up to the last round, but with only the first half of each round's seeds rendered. Then the last round's seed is rendered. Finally, the rounds are again rendered up to the last round, but this time the second half of each round's seeds are rendered.

code for example above: example/src/components/two-sided-single-elimination/index.tsx

[The-Kian]

This is awesome