Added public update() method that checks the file and re-reads properties if necessary.

src/helma/util/SystemProperties.java

@@ -97,6 +97,13 @@ public final class SystemProperties extends Properties {
         return Math.max(file.lastModified(), lastadd);
     }
 
+    /**
+     *  Update/re-read the properties from file if necessary.
+     */
+    public void update () {
+        checkFile();
+    }
+
     /**
      *  Return a checksum that changes when something in the properties changes.
      */