TAJO-972: Broadcast join with left outer join returns duplicated rows.(Hyoungjun Kim via jaehwa)

Closes #89
TAJO-969: Distributed sort on a large data set may result in incorrect results.

Closes #87
TAJO-914: join queries with constant values can cause schema mismatch in logical plan.

Closes #78
TAJO-968: Self-Join query (including partitioned table) doesn't run unexpectedly using auto broad cast join. (jaehwa)

Closes #88
TAJO-977: INSERT into a partitioned table as SELECT statement uses a wrong schema. (Hyoungjun Kim via hyunsik)

Closes #95
TAJO-974: Eliminate unexpected case condition in SubQuery. (Hyoungjun Kim via hyunsik)

Closes #974
TAJO-974: Eliminate unexpected case condition in SubQuery. (missed ticket close)

Closes #93
TAJO-952: Wrong default partition volume config. (Mai Hai Thanh via jihoon)
TAJO-980: execution page in Web UI broken.

Closes #97
TAJO-976: HashPartitioner doesn't make desired number of partitions infrequently. (Hyoungjun Kim via hyunsik)

Closes #94
TAJO-976: HashPartitioner doesn't make desired number of partitions infrequently. (Fixed a build failure due to 1.7 API)
Merge branch 'master' of http://git-wip-us.apache.org/repos/asf/tajo into index_support
TAJO-957: ROUND should be support INT parameter. (Mai Hai Thanh via hyunsik)
Merge branch 'master' of http://git-wip-us.apache.org/repos/asf/tajo into index_support