Added 'a11y' and 'source' addons to storybook as well as more stories

stories/FieldCheckbox.stories.js

@@ -0,0 +1,39 @@
+import React from 'react';
+import {useActionState} from './helper';
+import FieldCheckbox from '../src/components/FieldCheckbox';
+import {Wrapper} from './ui';
+import {withA11y} from '@storybook/addon-a11y';
+
+export default {
+  title: 'FieldCheckbox',
+  component: FieldCheckbox,
+  decorators: [withA11y],
+};
+
+
+export const BasicUnchecked = () => {
+  const [value, setValue] = useActionState("onChange", false);
+
+  return (
+    <Wrapper>
+      <FieldCheckbox
+        value={value}
+        onChange={setValue}
+      />
+    </Wrapper>
+  );
+};
+
+export const BasicChecked = () => {
+  const [value, setValue] = useActionState("onChange", true);
+
+  return (
+    <Wrapper>
+      <FieldCheckbox
+        value={value}
+        onChange={setValue}
+      />
+    </Wrapper>
+  );
+};
+