[PDI-11959] Hadoop Job Executor: Jobs using org.apache.hadoop.mapreduce API don't work

Changed Connection interface in shims.api to have ability to change ShimUtils in common project and to not lose backward compatibility 
To verify fix also need to replace pentaho-shims-api.jar in big data lib folder. 
Also fixed regression related to MapReduce job entry introduced by previous commit (https://github.com/stepanovdg/pentaho-hadoop-shims/commit/7e9ad7de8c134ad7e87bcf6f18e21ba185bf30ed).