[Store] Refactor VectorizerInterface to separate string and document vectorization

Author: OskarStark

config/options.php

@@ -373,6 +373,7 @@
                 ->end()
             ->end()
             ->arrayNode('vectorizer')
+                ->info('Vectorizers for converting strings to Vector objects and transforming TextDocument arrays to VectorDocument arrays')
                 ->useAttributeAsKey('name')
                 ->arrayPrototype()
                     ->children()