message: fix security issues around jackson-databind library
diff: <dependency>
  <groupId>com.fasterxml.jackson.core</groupId>
  <artifactId>jackson-databind</artifactId>
  - <version>2.9.1</version>
  + <version>2.9.7</version>
  </dependency>
  <dependency>
  <artifactId>maven-compiler-plugin</artifactId>
  <version>3.5.1</version>
  <configuration>
  - <source>1.7</source>
  - <target>1.7</target>
  + <source>1.8</source>
  + <target>1.8</target>
  </configuration>
  </plugin>
  <plugin>
  <plugin>
  <groupId>org.jacoco</groupId>
  <artifactId>jacoco-maven-plugin</artifactId>
  + <version>0.8.2</version>
  <executions>
  <execution>
  <goals>
  