SQOOP-972: Sqoop2: Load server URL from environment in shell

(Jarek Jarcec Cecho via Kate Ting)
SQOOP-967: Sqoop2: Introduce dummy configuration key to easily identify Sqoop2 job

(Jarek Jarcec Cecho via Kate Ting)
SQOOP-966: Sqoop2: Remove placeholder class IgnoredForm

(Jarek Jarcec Cecho via Kate Ting)