* add jq expression in the flattenSpec
* more tests
* add benchmark
* fix style
* use JsonNode for both JSONPath and JQ
* clean up
* more clean up
* add documentation
* fix style
* move jackson-jq version to dependencyManagement section. remove commented code
* oops. revert wrong fix
* throw IllegalArgumentException for JQ syntax error
* remove e.printStackTrace() that is forbidden
* touch