Like XStreamSolutionFileIO, but for Jackson.

Motivation: a lot of people use optaplanner as a REST service and only have JSON format support (= jackson annotations on their domain model).

Impl reqs:

• Use the jackson version of JEE 7, so the JSR standarized json annotations etc.
• In ProblemBenchmarksConfig.java, next to xStreamAnnotatedClassList, add jacksonAnnotatedClassList.
• Just like XStreamSolutionFileIOTest, add a JacksonSolutionFileIOTest
• Place code in optaplanner-persistence-jackson module instead of optaplanner-persistence-xstream module
• Reuse jackson's Score marshalling/unmarshalling (just like we reuse the xstream score one)