[SPARK-1406] Updated pmml model lib to 1.1.15, latest Java 6 compatible

Author: selvinsource

mllib/pom.xml

@@ -112,7 +112,7 @@
     <dependency>
     	<groupId>org.jpmml</groupId>
     	<artifactId>pmml-model</artifactId>
-    	<version>1.1.7</version>
+    	<version>1.1.15</version>
     </dependency>
   </dependencies>
   <profiles>