remove hadoop.job.ugi and kerberos principal hardcoded injections

This is a follow up of OOZIE-754 to remove unneeded props being set in the Hadoop conf files.

The hadoop.job.ugi was being set for Hadoop 0.20 an earlier versions. It is of now use nowadays.

The Kerberos principals were injected because certain versions of hadoop didn't have them as default this is actually a bug as the injected value is hardcoded. Given that now Hadoop configurations per cluster can be set in the HadoopAccessor, if needed, this properties should be set there.