Tag documentation wrong in Github readme

[ubergraham]

<slot name="tag" let:label let:item let:unselectItem>
  <span class="tag">{label}</span>
  <span class="delete-tag" on:click|preventDefault="{unselectItem(item)}"></span>
</slot>

Should be replaced with

<div slot="tag">
...
</div>

[pstanoev]

Fixed.