refactor: use $$restProps API

- add ref prop for applicable components (#196)
- add slot to Content Switcher `Switch` component (#183)
- remove fillArray, css utilities

src/components/Icon/Icon.svelte

@@ -1,40 +1,27 @@
 <script>
-  let className = undefined;
-  export { className as class };
-  export let focusable = false;
   export let render = undefined;
   export let skeleton = false;
-  export let style = undefined;
-  export let tabindex = undefined;
-  export let title = undefined;
 
-  import IconSkeleton from './Icon.Skeleton.svelte';
+  import IconSkeleton from "./Icon.Skeleton.svelte";
 
-  $: iconName = render.toString().split(' ')[1];
+  $: iconName = render.toString().split(" ")[1];
   $: size = parseInt(iconName.slice(-2), 10);
 </script>
 
 {#if skeleton}
   <IconSkeleton
+    {size}
+    {...$$restProps}
     on:click
     on:mouseover
     on:mouseenter
-    on:mouseleave
-    class={className}
-    {style}
-    {size} />
+    on:mouseleave />
 {:else}
   <svelte:component
     this={render}
-    aria-label={$$props['aria-label']}
-    aria-labelledby={$$props['aria-labelledby']}
+    {...$$restProps}
     on:click
     on:mouseover
     on:mouseenter
-    on:mouseleave
-    class={className}
-    {tabindex}
-    {focusable}
-    {style}
-    {title} />
+    on:mouseleave />
 {/if}