Reset excluded groups when calling prepare method (see #98)

* Reset excluded options on prepare 51b2de6

Co-authored-by: Daniele Sciannimanica <[email protected]>

src/StyleManager/Styles.php

@@ -86,6 +86,7 @@ public function prepare($identifier, $arrGroups=null): Styles
     {
         $this->currIdentifier = $identifier;
         $this->currGroups     = $arrGroups;
+        $this->exclGroups     = null;
 
         return $this;
     }