Add Movlw instruction (#7)

commands/Movlw.java

@@ -0,0 +1,19 @@
+package commands;
+
+import registers.Memory;
+
+public class Movlw extends CommandUtils implements Command
+{
+    private final int literal;
+
+    public Movlw(int input)
+    {
+        literal = input & 0x00FF;
+    }
+
+    @Override
+    public void execute()
+    {
+        Memory.workingRegister = literal;
+    }
+}

decoder/CommandDecoder.java

@@ -1,9 +1,6 @@
 package decoder;
 
-import commands.Addlw;
-import commands.Andlw;
-import commands.Command;
-import commands.Iorlw;
+import commands.*;
 
 public class CommandDecoder
 {
@@ -115,8 +112,7 @@ public class CommandDecoder
         switch(input & 0x3C00)
         {
             case 0x3000:
-                //movlw();
-                break;
+                return new Movlw(input);
             case 0x3400:
                 //retlw();
                 break;