remove md5_s from default index fields

it is not assigned a value / not used
Due to above also excluded from transfer protocol.

defaults/solr.collection.schema

@@ -51,8 +51,8 @@ title
 ## id of the host, a 6-byte hash that is part of the document id (mandatory field)
 host_id_s
 
-## the md5 of the raw source (mandatory field)
-md5_s
+## the md5 of the raw source
+#md5_s
 
 ## the 64 bit hash of the org.apache.solr.update.processor.Lookup3Signature of text_t
 exact_signature_l

source/net/yacy/kelondro/data/meta/URIMetadataNode.java

@@ -130,7 +130,7 @@ public class URIMetadataNode extends SolrDocument /* implements Comparable<URIMe
             this.setField(CollectionSchema.fresh_date_dt.name(), new Date());
         }
         this.setField(CollectionSchema.referrer_id_s.name(), prop.getProperty("referrer", ""));
-        this.setField(CollectionSchema.md5_s.name(), prop.getProperty("md5", ""));
+        // this.setField(CollectionSchema.md5_s.name(), prop.getProperty("md5", "")); // always 0 (not used / calculated)
         this.setField(CollectionSchema.size_i.name(), Integer.parseInt(prop.getProperty("size", "0")));
         this.setField(CollectionSchema.wordcount_i.name(), Integer.parseInt(prop.getProperty("wc", "0")));
         final String dt = prop.getProperty("dt", "t");
@@ -531,7 +531,7 @@ public class URIMetadataNode extends SolrDocument /* implements Comparable<URIMe
             s.append(",load=").append(formatter.format(this.loaddate()));
             s.append(",fresh=").append(formatter.format(this.freshdate()));
             s.append(",referrer=").append(this.referrerHash() == null ? "" : ASCII.String(this.referrerHash()));
-            s.append(",md5=").append(this.md5());
+            //s.append(",md5=").append(this.md5()); // md5 never calculated / not used, also removed from this(prop) 2015-11-27
             s.append(",size=").append(this.filesize());
             s.append(",wc=").append(this.wordCount());
             final char dt = this.doctype();