Update docs to use renamed commands & add example for tags (#67)

Author: adeboyed

docs-src/index.md

@@ -66,11 +66,11 @@ $bookIndex->add([
 ```php-inline
 $result = $bookIndex->search('two cities');
 
-$result->count();     // Number of documents.
-$result->documents(); // Array of matches.
+$result->getCount();     // Number of documents.
+$result->getDocuments(); // Array of matches.
 
 // Documents are returned as objects by default.
-$firstResult = $result->documents()[0];
+$firstResult = $result->getDocuments()[0];
 $firstResult->title;
 $firstResult->author;
 ```

docs-src/indexing.md

@@ -63,6 +63,7 @@ $document->title->setValue('How to be awesome.');
 $document->author->setValue('Jack');
 $document->price->setValue(9.99);
 $document->place->setValue(new GeoLocation(-77.0366, 38.8977));
+$document->color->setValue(new Tag('red'));
 
 $this->add($document);
 ```