Abstract Gate added

Author: Rúben André Barreiro

src/main/java/org/quisl/framework/java/instructions/gates/Gate.java

@@ -2,13 +2,13 @@
 
 public abstract class Gate {
 
-    private Integer numInputs;
+    private final Integer numInputs;
 
-    private Integer numOutputs;
+    private final Integer numOutputs;
 
-    private String prefix;
+    private final String prefix;
 
-    private String gateName;
+    private final String gateName;
 
 
     public Gate(Integer numInputs, Integer numOutputs,
@@ -47,4 +47,6 @@ public String getGateName() {
 
     }
 
+    public abstract void applyGate();
+
 }