Improve logging

src/org/helioviewer/jhv/base/logging/Log.java

@@ -1,21 +1,27 @@
 package org.helioviewer.jhv.base.logging;
 
+import org.helioviewer.jhv.base.time.TimeUtils;
+
 public class Log {
 
+    private static String format(String s) {
+        return TimeUtils.format(System.currentTimeMillis()) + " [" + Thread.currentThread().getName() + "] " + s;
+    }
+
     public static void warn(Object obj) {
-        System.err.println(obj.toString());
+        System.err.println(format("WARN " + obj.toString()));
     }
 
     public static void error(Object obj) {
-        System.err.println(obj.toString());
+        System.err.println(format("ERROR " + obj.toString()));
     }
 
     public static void error(Object obj, Throwable error) {
-        System.err.println(obj.toString() + error.toString());
+        System.err.println(format("ERROR " + obj.toString() + error.toString()));
     }
 
     public static void debug(Object obj) {
-        System.out.println(obj.toString());
+        System.out.println(format("DEBUG " + obj.toString()));
     }
 
 }

src/org/helioviewer/jhv/io/DataSourcesTask.java

@@ -33,7 +33,7 @@ public void run() {
             JSONObject json = JSONUtils.getJSONStream(new DownloadStream(url).getInput());
             schema.validate(json);
         } catch (Exception e) {
-            Log.error(e);
+            Log.error(url + " : " + e);
         }
     }