caskdata/cdap — pull request #648 by anew (2014-11-20 01:27:26+00:00)
Title: Feature/file ds

- adds a File dataset interface, also Input/OutputFormatProvider
- an implementation named FileDataset, including a definition and admin
- Map/reduce runner to support Input/OutputFormatProvider in addition to BatchReadable/Writable
- utilities for scoped runtime arguments ("dataset..my.property").
- unit tests

Please give feedback especially about the APIs.