Load datasets + Datasets grid + Datasets search (#889)

* [examples/openspending][m] - added loader + fetching from datapackage

- Also added an indexing example

* [examples/openspending,home][xl]: removes datasets table, implement dataset cards grid, implement country facet

* [examples/openspending,home][m]: add min date and max date facets

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Co-authored-by: Luccas Mateus de Medeiros Gomes <luccasmmg@gmail.com>

examples/openspending/components/Header.tsx

@@ -46,7 +46,6 @@ export function Header() {
             </li>))}
         </ul>
         <div className="hidden sm:mt-10 sm:flex lg:mt-0 lg:grow lg:basis-0 lg:justify-end">
-          <Button href="#">View on GitHub</Button>
         </div>
       </Container>
     </header >