MAHOUT-1579 Implement a data model which can load data from hadoop files...

Now mahout deal with the data which stored in hdfs, it should run mapred job.
I Implement a data model which can load data from hadoop filesystem directly, 
and process data like FileDataModel.
I'm not comfortable with adding all that stuff just for the mini cluster. Could you rewrite your tests to simply use the local filesystem via Hadoop's Path API? That should be sufficient.