exclude default search fields from text copy to text_t

for metadata index documents (reduce text redundance)

source/net/yacy/search/schema/CollectionConfiguration.java

@@ -333,12 +333,12 @@ public class CollectionConfiguration extends SchemaConfiguration implements Seri
         	// construct the text from other metadata parts.
         	// This is necessary here since that is used to search the link when no other data (parsed text body) is available
         	StringBuilder sb = new StringBuilder(120);
-        	accText(sb, md.dc_title());
+        	// accText(sb, md.dc_title()); // default search field via getQueryFields(), not needed for snippet (always displayed)
         	accText(sb, md.dc_creator());
         	accText(sb, md.dc_publisher());
-        	accText(sb, md.snippet());
+        	// accText(sb, md.snippet()); // above added to description_txt, default search field via getQueryFields(), description_txt incl. in snippet calculation
         	accText(sb, md.url().toTokens());
-        	accText(sb, keywords);
+        	accText(sb, keywords); // default search field via getQueryFields(), keywords not incl. in snippet calculation
         	add(doc, CollectionSchema.text_t, sb.toString());
         }