Added code for reflective avro types.
Introduced CREATE and OVERWRITE file output write modes. OVERWRITE is default (as before).
Rewrote code for file output path preparation.
Fixed distributed writing to local filesystem #286
Added test for write modes on local file system
Updated configuration keys to new naming
Added optional parameter to always write into directories even in case of DOP = 1.
Extended FileOutputFormatTest.
Some code beautifications.