Update to Spring IO version

- Update Spring Boot 1.2.3.RELEASE
- Update Spring Security 4.0.0.RELEASE
- Update Spring 4.1.6.RELEASE
- Update Groovy 2.3.8
- Update Jackson 2.4.5
- Update Jedis 2.5.2
- Update Spring Data Redis 1.4.2

Fixes gh-126

samples/httpsession/build.gradle

@@ -14,7 +14,7 @@ dependencies {
 
 	providedCompile "javax.servlet:javax.servlet-api:$servletApiVersion"
 
-	testCompile 'junit:junit:4.11'
+	testCompile "junit:junit:$junitVersion"
 
 	integrationTestCompile gebDependencies
 }