etl.default.timezone not respected

It seems that ```EtlMultiOutputFormat``` is configured to read in ```etl.default.timezone```  from a camus.properties file, but no where is this value actually used.  

```DefaultPartitioner``` manually sets ```DateTimeFormatter OUTPUT_DATE_FORMAT``` by calling ```DateUtils
            .getDateTimeFormatter("YYYY/MM/dd/HH")``` method without the second argument ```DateTimeZone timeZone```.  Without a timezone, DateUtils defaults to PST.


I'd submit a pull request to make DateUtils respect the value of ```etl.default.timezone```, but I'm not sure how best to do this.  ```DateUtils``` doesn't have any method that takes a ```JobContext```.  I could make```DefaultPartitioner.generatePartitionedPath``` call ```getDateTimeFormatter(String str, DateTimeZone timeZone)``` instead of using the final PST ```OUTPUT_DATE_FORMAT````, but perhaps this will result in too many calls for a config property that only needs to be set once.


I've run into similar issues when trying to add config properties to my concrete ```RecordWriterProvider``` implementation.  I think this issue and the ones I am running into could be alleviated if the interfaces had constructors that took JobContext objects as arguments, and ```EtlMultiOutputFormat``` would call them with its JobContext object.  Then implementers could save whatever properties they wanted when the concrete instance was instantiated for use later.