jobFilePreprocessor.sh incorrectly setting HADOOP_CLASSPATH

In a CDH4 environment, running jobFilePreprocessor fails with missing class stack traces.  It was resolved by ensuring that HADOOP_CLASSPATH contained both the output for $(hbase classpath) and $(hadoop classpath).  Since the docs state that we should be ensuring that HRAVEN_CLASSPATH should contain these, let's go ahead and default to setting our HADOOP_CLASSPATH in the script to this.