Refactor endpoints to allow retrieving set queries or filters.

src/SearchEndpoint/AbstractSearchEndpoint.php

src/SearchEndpoint/AggregationsEndpoint.php

src/SearchEndpoint/BuilderContainerAwareTrait.php

src/SearchEndpoint/FilterEndpoint.php

src/SearchEndpoint/HighlightEndpoint.php

src/SearchEndpoint/PostFilterEndpoint.php

src/SearchEndpoint/QueryEndpoint.php

src/SearchEndpoint/SearchEndpointInterface.php

src/SearchEndpoint/SortEndpoint.php

tests/SearchEndpoint/AggregationsEndpointTest.php

tests/SearchEndpoint/BuilderContainerAwareTraitTest.php

tests/SearchEndpoint/FilterEndpointTest.php

tests/SearchEndpoint/HighlightEndpointTest.php

tests/SearchEndpoint/PostFilterEndpointTest.php

tests/SearchEndpoint/QueryEndpointTest.php

tests/SearchEndpoint/SearchEndpointFactoryTest.php