[sql]use SparkSQLEnv.stop() in ShutdownHook

Author: wangfei <wangfei1@huawei.com>

Closes #1852 from scwf/patch-3 and squashes the following commits:

ae28c29 [wangfei] use SparkSQLEnv.stop() in ShutdownHook
[SQL] A tiny refactoring in HiveContext#analyze

I should use `EliminateAnalysisOperators` in  `analyze` instead of manually pattern matching.

Author: Yin Huai <huaiyin.thu@gmail.com>

Closes #1881 from yhuai/useEliminateAnalysisOperators and squashes the following commits:

f3e1e7f [Yin Huai] Use EliminateAnalysisOperators.
[SPARK-2965][SQL] Fix HashOuterJoin output nullabilities.

Output attributes of opposite side of `OuterJoin` should be nullable.

Author: Takuya UESHIN <ueshin@happy-camper.st>

Closes #1887 from ueshin/issues/SPARK-2965 and squashes the following commits:

bcb2d37 [Takuya UESHIN] Fix HashOuterJoin output nullabilities.
[SPARK-2968][SQL] Fix nullabilities of Explode.

Output nullabilities of `Explode` could be detemined by `ArrayType.containsNull` or `MapType.valueContainsNull`.

Author: Takuya UESHIN <ueshin@happy-camper.st>

Closes #1888 from ueshin/issues/SPARK-2968 and squashes the following commits:

d128c95 [Takuya UESHIN] Fix nullability of Explode.
[SPARK-2650][SQL] Build column buffers in smaller batches

Author: Michael Armbrust <michael@databricks.com>

Closes #1880 from marmbrus/columnBatches and squashes the following commits:

0649987 [Michael Armbrust] add test
4756fad [Michael Armbrust] fix compilation
2314532 [Michael Armbrust] Build column buffers in smaller batches
[SQL] [SPARK-2826] Reduce the memory copy while building the hashmap for HashOuterJoin

This is a follow up for #1147 , this PR will improve the performance about 10% - 15% in my local tests.
```
Before:
LeftOuterJoin: took 16750 ms ([3000000] records)
LeftOuterJoin: took 15179 ms ([3000000] records)
RightOuterJoin: took 15515 ms ([3000000] records)
RightOuterJoin: took 15276 ms ([3000000] records)
FullOuterJoin: took 19150 ms ([6000000] records)
FullOuterJoin: took 18935 ms ([6000000] records)

After:
LeftOuterJoin: took 15218 ms ([3000000] records)
LeftOuterJoin: took 13503 ms ([3000000] records)
RightOuterJoin: took 13663 ms ([3000000] records)
RightOuterJoin: took 14025 ms ([3000000] records)
FullOuterJoin: took 16624 ms ([6000000] records)
FullOuterJoin: took 16578 ms ([6000000] records)
```

Besides the performance improvement, I also do some clean up as suggested in #1147

Author: Cheng Hao <hao.cheng@intel.com>

Closes #1765 from chenghao-intel/hash_outer_join_fixing and squashes the following commits:

ab1f9e0 [Cheng Hao] Reduce the memory copy while building the hashmap