further avoid to set connect info properties as header value

following comment "use of properties as header values is discouraged"
in case where (proxy)HTTPClient overwrites values with supplied url.
Use defined request.referer procedure in response class.

source/net/yacy/crawler/retrieval/Response.java

@@ -791,24 +791,14 @@ public class Response {
 
     public DigestURL referrerURL() {
         if (this.requestHeader == null) return null;
-        try {
-            final String r = this.requestHeader.get(RequestHeader.REFERER, null);
-            if (r == null) return null;
-            return new DigestURL(r);
-        } catch (final Exception e) {
-            return null;
-        }
+        return this.requestHeader.referer();
     }
 
     public byte[] referrerHash() {
         if (this.requestHeader == null) return null;
-        final String u = this.requestHeader.get(RequestHeader.REFERER, "");
-        if (u == null || u.isEmpty()) return null;
-        try {
-            return new DigestURL(u).hash();
-        } catch (final Exception e) {
-            return null;
-        }
+        final DigestURL url = this.requestHeader.referer();
+        if (url == null) return null;
+        return url.hash();
     }
 
     public boolean validResponseStatus() {

source/net/yacy/http/servlets/UrlProxyServlet.java

@@ -154,9 +154,6 @@ public class UrlProxyServlet extends HttpServlet implements Servlet {
         prop.put(HeaderFramework.CONNECTION_PROP_CLIENTIP, Domains.LOCALHOST);
         prop.put(HeaderFramework.CONNECTION_PROP_CLIENT_HTTPSERVLETREQUEST, request);
 
-        yacyRequestHeader.put(HeaderFramework.HOST, hostwithport );
-        yacyRequestHeader.put(HeaderFramework.CONNECTION_PROP_PATH, proxyurl.getPath());
-
         // 4 & 5 get & index target url
         final ByteArrayOutputStream tmpproxyout = new ByteArrayOutputStream();
         HTTPDProxyHandler.doGet(prop, yacyRequestHeader, tmpproxyout, ClientIdentification.yacyProxyAgent);

source/net/yacy/http/servlets/YaCyProxyServlet.java

@@ -125,9 +125,6 @@ public class YaCyProxyServlet extends HttpServlet implements Servlet {
         prop.put(HeaderFramework.CONNECTION_PROP_CLIENTIP, Domains.LOCALHOST);
         prop.put(HeaderFramework.CONNECTION_PROP_CLIENT_HTTPSERVLETREQUEST, request);
 
-        yacyRequestHeader.put(HeaderFramework.HOST, hostwithport );
-        yacyRequestHeader.put(HeaderFramework.CONNECTION_PROP_PATH, proxyurl.getPath());
-
         final ByteArrayOutputStream tmpproxyout = new ByteArrayOutputStream();
         HTTPDProxyHandler.doGet(prop, yacyRequestHeader, tmpproxyout, ClientIdentification.yacyProxyAgent);
         

source/net/yacy/server/http/HTTPDProxyHandler.java

@@ -256,7 +256,8 @@ public final class HTTPDProxyHandler {
     }
 
     /**
-     * Get a page from the remote server as proxy request for the client
+     * Get a page from the remote server as proxy request for the client.
+     * The target url is expected in the conProp CONNECTION_PROP_DIGESTURL
      *
      * @param conProp a collection of properties about the connection, like URL
      * @param requestHeader The header lines of the connection from the request
@@ -298,8 +299,6 @@ public final class HTTPDProxyHandler {
                     log.finest(reqID + "    using redirector to " + url);
                 }
                 conProp.put(HeaderFramework.CONNECTION_PROP_DIGESTURL, url);
-                requestHeader.put(HeaderFramework.HOST, url.getHost() + ":" + url.getPort());
-                requestHeader.put(HeaderFramework.CONNECTION_PROP_PATH, url.getPath());
             }
 
 
@@ -401,7 +400,7 @@ public final class HTTPDProxyHandler {
      * Get requested proxied page from the web
      *
      * @param conProp
-     * @param url
+     * @param url requested target url
      * @param requestHeader
      * @param cachedResponseHeader
      * @param respond