Update to Jackson 2.8.4

Fixes gh-4122

gradle/javaprojects.gradle

@@ -21,7 +21,7 @@ ext.groovyVersion = '2.4.4'
 ext.hsqlVersion = '2.3.2'
 ext.hibernateVersion = '5.0.11.Final'
 ext.hibernateValidatorVersion = '5.2.4.Final'
-ext.jacksonDatavindVersion = '2.8.3'
+ext.jacksonDatavindVersion = '2.8.4'
 ext.javaPersistenceVersion = '2.1.1'
 ext.jettyVersion = '6.1.26'
 ext.jstlVersion = '1.2.1'