Make LogoutRequest and LogoutResponse more extensible

This increases the visibility of LogoutResponse.query() to protected
and adds setValidationException to both LogoutResponse and LogoutRequest
to ease the development of extension classes that need to customize the
validation process.

Author: mauromol

core/src/main/java/com/onelogin/saml2/logout/LogoutRequest.java

@@ -758,6 +758,16 @@ public Exception getValidationException() {
 		return validationException;
 	}
 
+	/**
+	 * Sets the validation exception that this {@link LogoutRequest} should return
+	 * when a validation error occurs.
+	 * 
+	 * @param validationException
+	 *              the validation exception to set
+	 */
+	protected void setValidationException(Exception validationException) {
+		this.validationException = validationException;
+	}
 
 	/**
 	 * @return the ID of the Logout Request

core/src/main/java/com/onelogin/saml2/logout/LogoutResponse.java

@@ -338,14 +338,15 @@ public SamlResponseStatus getSamlResponseStatus() throws ValidationError
     }
 
 	/**
-     * Extracts nodes that match the query from the DOMDocument (Logout Response Menssage)
-     *
-     * @param query
-     *				Xpath Expression
-     *
-     * @return DOMNodeList The queried nodes
-     */
-	private NodeList query (String query) throws XPathExpressionException {
+       * Extracts nodes that match the query from the DOMDocument (Logout Response Menssage)
+       *
+       * @param query
+       *				Xpath Expression
+       *
+       * @return DOMNodeList The queried nodes
+	 * @throws XPathExpressionException 
+       */
+	protected NodeList query (String query) throws XPathExpressionException {
 		return Util.query(this.logoutResponseDocument, query, null);
 	}
 
@@ -475,4 +476,15 @@ public String getError() {
 	public Exception getValidationException() {
 		return validationException;
 	}
+	
+	/**
+	 * Sets the validation exception that this {@link LogoutResponse} should return
+	 * when a validation error occurs.
+	 * 
+	 * @param validationException
+	 *              the validation exception to set
+	 */
+	protected void setValidationException(Exception validationException) {
+		this.validationException = validationException;
+	}
 }