Convert TFile unit test to DTFile unit test
Merge branch 'dt-dev' of github.com:DataTorrent/Malhar into dt-dev
Merge branch 'dt-dev' of github.com:DataTorrent/Malhar into dt-dev
Merge branch 'dt-dev' of github.com:DataTorrent/Malhar into dt-dev
Merge pull request #1134 from siyuanh/dt-dev

Convert TFile unit test to DTFile unit test