implemented decfsz Instruction

de/darkress/pic16f84sim/commands/Decfsz.java

@@ -22,6 +22,12 @@ public class Decfsz extends FileRegisterCommandUtils implements Command
         checkZeroBit(result);
 
         writeToDestination(destinationBit, address, result % 256); // Catch underflow
+
+        if((result % 256) == 0)
+        {
+            Nop nop = new Nop();
+            nop.execute();
+        }
         ProgramCounter.incPC();
     }
 }