TAJO-1128: Implement a select box for database at web interface. (Jongyoung Park via hyunsik)

Closes #222
TAJO-1026: Implement Query history persistency manager.

Closes #179
TAJO-1162: to_char() returns "-00" second.

Closes #234
TAJO-1161: Remove joda time dependency from tajo-core. (Jihun Kang via hyunsik)

Closes #233
TAJO-1109: Separate SQL Statements from Catalog Stores. (Jihun Kang via hyunsik)

Closes #201
Merge branch 'master' of https://git-wip-us.apache.org/repos/asf/tajo into TAJO-1151

Conflicts:
	tajo-common/pom.xml
TAJO-1152: RawFile ByteBuffer should be reuse. (jinho)

Closes #224
Merge branch 'master' of https://git-wip-us.apache.org/repos/asf/tajo into TAJO-1151
remove commented out line