Upgrade Jackson version

Author: garyrussell

build.gradle

@@ -72,7 +72,7 @@ subprojects { subproject ->
 	ext {
 		assertjVersion = '2.6.0'
 		hamcrestVersion = '1.3'
-		jacksonVersion = '2.9.1'
+		jacksonVersion = '2.9.8'
 		junitVersion = '4.12'
 		kafkaVersion = '0.11.0.2'
 		mockitoVersion = '2.9.0'