TAJO-435: Improve intermediate file. (jinho)
TAJO-442: Cast operator with nested functions causes NPE. (hyunsik)
TAJO-436: Implement ceiling(FLOAT8) function. (DaeMyung Kang via hyunsik)
TAJO-382: Implement encode/decode functions. (Seungun Choe via jihoon)
TAJO-431: HCatalogStore can't write any data using INSERT OVERWRITE clause. (jaehwa)
TAJO-182: Correct NULL value handling of primitive operators. (hyunsik)
TAJO-437: Timestamp literal support. (hyunsik)
TAJO-450: Incorrect inet4datum comparison. (jinho)
Merge branch 'master' of https://git-wip-us.apache.org/repos/asf/incubator-tajo into TAJO-428