added 'empty' commands (e.g /stop)

com/nemez/cmdmgr/component/EmptyComponent.java

@@ -0,0 +1,19 @@
+package com.nemez.cmdmgr.component;
+
+public class EmptyComponent extends ArgumentComponent {
+
+	@Override
+	public Object get(String input) {
+		return "";
+	}
+
+	@Override
+	public boolean valid(String input) {
+		return true;
+	}
+	
+	@Override
+	public String getComponentInfo() {
+		return "<empty>";
+	}
+}