TAJO-1025: Network disconnection during query processing can cause infinite exceptions. (Jihun Kang via jinho)
TAJO-983: Worker should directly read Intermediate data stored in localhost rather than fetching. (Mai Hai Thanh via hyunsik)
TAJO-1067: INSERT OVERWRITE INTO should not remove all partitions.
Merge branch 'master' of https://git-wip-us.apache.org/repos/asf/tajo into TAJO-1067