adds synchornized dumplog

source/net/yacy/search/query/AccessTracker.java

@@ -191,12 +191,16 @@ public class AccessTracker {
     public static void dumpLog() {
         lastLogDump = System.currentTimeMillis();
     	localCount += localSearches.size();
-        while (!localSearches.isEmpty()) {
-            addToDump(localSearches.removeFirst(), 0);
-        }
+    	synchronized (localSearches) {
+    	    while (!localSearches.isEmpty()) {
+                addToDump(localSearches.removeFirst(), 0);
+            }
+    	}
         remoteCount += remoteSearches.size();
-        while (!remoteSearches.isEmpty()) {
-            addToDump(remoteSearches.removeFirst(), 0);
+        synchronized (remoteSearches) {
+            while (!remoteSearches.isEmpty()) {
+                addToDump(remoteSearches.removeFirst(), 0);
+            }
         }
         Thread t = new Thread("AccessTracker.dumpLog") {
             @Override