pom.xml: update Jetty to 9.2.18.v20160721

No functional changes.

Author: php-coder

pom.xml

@@ -404,7 +404,7 @@
 		<javax.validation.version>1.1.0.Final</javax.validation.version>
 
 		<!-- Redefine default value from spring-boot-dependencies (https://git.io/vKAiK) -->
-		<jetty.version>9.2.17.v20160517</jetty.version>
+		<jetty.version>9.2.18.v20160721</jetty.version>
 
 		<!-- Don't forget to update version in MvcConfig and Url classes -->
 		<jquery.version>1.9.1</jquery.version>