Adjust metrics of styled accidentals.

Adding width to calculation does not affect the `getKeyWidth` and `getKeyLeft` methods.

Dedicate caches to same functions

This is to cover repainting of keys using the widths.

Prefer using React memoization instead of mem when using inside React.

Add memoization to expensive pure functions because the library involves a lot of computation under the hood.

Demonstrate scaling of detail in styled key set.

Make custom theme scalable and more flexible in terms of customization.

Export styled keys for customization of the component.

Use custom styled keys and add pressed keys for styled key set.

Refer to URL in comment for details.

Add styled keyboard made out of scalable HTML elements.

Add files generated from tsdx.