Add compile dependency to commons-logging (#476)

gradle.properties

@@ -1,4 +1,5 @@
 bootstrapVersion=2.2.2
+commonsLoggingVersion=1.2
 commonsPoolVersion=2.4.2
 jacksonVersion=2.6.5
 jspApiVersion=2.0

spring-session/build.gradle

@@ -15,6 +15,7 @@ configurations {
 }
 
 dependencies {
+	compile "commons-logging:commons-logging:$commonsLoggingVersion"
 	optional "org.springframework.data:spring-data-redis:$springDataRedisVersion",
 			"com.hazelcast:hazelcast:$hazelcastVersion",
 			"org.springframework.data:spring-data-gemfire:$springDataGemFireVersion",