the commit for 0.3
Removed some obsolete libraries (commons.collections, hbase).
RESOLVED - TAJO-264: 테스트 시 발생하는 "Can not create a Path from a null
string" 오류 수정
Merged in hyunsik/nta (pull request #1)
Fixed DatumType of ByteArrayDatum and Removed TestByteArrayDatum that causes the error.
Fixed the wrong location of engine-default.xml.
Corrected the wrong constant (MASTER_PORT -> MASTER_HOME)
Merged in hyunsik/nta (pull request #2)
TAJO-262: 분산 엔진 마스터와 LocalEngine간의 RPC 인터페이스 설계
https://dbserver.korea.ac.kr/jira/browse/TAJO-262
Fixed the unit test bug and applied trivial changes.
Merged in hyunsik/nta (pull request #3)
TAJO-269: LocalEngineCluster 구현 
https://dbserver.korea.ac.kr/jira/browse/TAJO-269
Merged in hyunsik/nta (pull request #4)
TAJO-265 RawFile을 close() 후 addTuple() 호출 시 ReadOnlyException()을 throw 하도록 수정
TAJO-271 FileReader, FileWriter interface 구현
FileWriter / FileReader 이름 변경
Merged in jihoonson/nta (pull request #6)
TAJO-273: NtaTestingUtility의 리펙토링

https://dbserver.korea.ac.kr/jira/browse/TAJO-273
Merged in hyunsik/nta (pull request #8)
TAJO-276: NtaTestingUtility에 Zookeeper 클러스터 추가
https://dbserver.korea.ac.kr/jira/browse/TAJO-276