SQOOP-1121. Sqoop2: Serialize schema and make them available in the MR job.

(Jarek Jarcec Cecho via Hari Shreedharan)
SQOOP-1131. New test added in SQOOP-1121 is using unsupported API in Hadoop 100

(Jarek Jarcec Cecho via Hari Shreedharan)