OOM log tweak

router/java/src/net/i2p/router/tasks/OOMListener.java

 package net.i2p.router.tasks;
 
+import java.io.File;
 import java.util.concurrent.atomic.AtomicBoolean;
 
 import net.i2p.router.Router;
@@ -48,7 +49,8 @@ public class OOMListener implements I2PThread.OOMEventListener {
             log.log(Log.CRIT, "free mem: " + Runtime.getRuntime().freeMemory() + 
                               " total mem: " + Runtime.getRuntime().totalMemory());
             if (_context.hasWrapper())
-                log.log(Log.CRIT, "To prevent future shutdowns, increase wrapper.java.maxmemory in $I2P/wrapper.config");
+                log.log(Log.CRIT, "To prevent future shutdowns, increase wrapper.java.maxmemory in " +
+                                  _context.getBaseDir() + File.separatorChar + "wrapper.config");
         } catch (OutOfMemoryError oome) {}
         try { 
             ThreadDump.dump(_context, 1);