Fixed FMLRelaunchLog's Newline Handling

System.out.println("\n") causes currentMessage to start with a newline character, which means idx will always be 0 from then on. Therefore if idx is 0 messages must still be logged, otherwise no more messages sent to stdout will be logged and they will just accumulate in currentMessage.

fml/common/cpw/mods/fml/relauncher/FMLRelaunchLog.java

@@ -113,7 +113,7 @@ public class FMLRelaunchLog
                 // Are we longer than just the line separator?
                 int lastIdx = -1;
                 int idx = currentMessage.indexOf("\n",lastIdx+1);
-                while (idx > 0)
+                while (idx >= 0)
                 {
                     log.log(Level.INFO, currentMessage.substring(lastIdx+1,idx));
                     lastIdx = idx;