Add gson explicitly (it's going to go away in s-c-function)

Author: Dave Syer

pom.xml

@@ -51,6 +51,10 @@
 				</exclusion>
 			</exclusions>
 		</dependency>
+		<dependency>
+			<groupId>com.google.code.gson</groupId>
+			<artifactId>gson</artifactId>
+		</dependency>
 		<dependency>
 			<groupId>org.slf4j</groupId>
 			<artifactId>slf4j-jdk14</artifactId>