This patch adds a warning that when using WSL we're limited to 16 colors. It took me about 4 hours debugging why it didn't work, and this patch hopefully prevents others from wasting 4 hours.

MouseWheelEvent is deprecated and was removed with TypeScript 3.2, however, MouseWheelEvent is still aliased to WheelEvent. For more info see https://github.com/Microsoft/TSJS-lib-generator/pull/579

This PR fixes the build with TypeScript 3.2 by checking the object properties.