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)
TAJO-957: ROUND should be support INT parameter. (Mai Hai Thanh via hyunsik)
TAJO-978: RoundFloat8 should return Float8Datum type. (Hyoungjun Kim via hyunsik)

Closes #96
TAJO-979: Dividing float value by zero should throw "Divide by zero Exception" (Hyoungjun Kim via hyunsik)

Closes #100
TAJO-987: Hash shuffle should be balanced according to intermediate volumes.

Closes #101
Merge branch 'master' of https://git-wip-us.apache.org/repos/asf/tajo into TAJO-966