1.0.0

1.0.0 fixes the messy state of HKModal, making it a fully-controlled component once more.

Instead of taking a footer prop with arbitrary content, you can now pass an (optional) array of buttons in the buttons prop.

• Adds stories which show how to use buttons
• Adds an example story for a modal with a type-to-confirm mechanic
• Documents HKModal in the readme.