[SPARK-2994][SQL] Support for udfs that take complex types

Author: Michael Armbrust <michael@databricks.com>

Closes #1915 from marmbrus/arrayUDF and squashes the following commits:

a1c503d [Michael Armbrust] Support for udfs that take complex types
[SPARK-2650][SQL] More precise initial buffer size estimation for in-memory column buffer

This is a follow up of #1880.

Since the row number within a single batch is known, we can estimate a much more precise initial buffer size when building an in-memory column buffer.

Author: Cheng Lian <lian.cs.zju@gmail.com>

Closes #1901 from liancheng/precise-init-buffer-size and squashes the following commits:

d5501fa [Cheng Lian] More precise initial buffer size estimation for in-memory column buffer
[SPARK-2935][SQL]Fix parquet predicate push down bug

Author: Michael Armbrust <michael@databricks.com>

Closes #1863 from marmbrus/parquetPredicates and squashes the following commits:

10ad202 [Michael Armbrust] left <=> right
f249158 [Michael Armbrust] quiet parquet tests.
802da5b [Michael Armbrust] Add test case.
eab2eda [Michael Armbrust] Fix parquet predicate push down bug
[SPARK-2970] [SQL] spark-sql script ends with IOException when EventLogging is enabled

Author: Kousuke Saruta <sarutak@oss.nttdata.co.jp>

Closes #1891 from sarutak/SPARK-2970 and squashes the following commits:

4a2d2fe [Kousuke Saruta] Modified comment style
8bd833c [Kousuke Saruta] Modified style
6c0997c [Kousuke Saruta] Modified the timing of shutdown hook execution. It should be executed before shutdown hook of o.a.h.f.FileSystem
[SPARK-2986] [SQL] fixed: setting properties does not effect

it seems that set command does not run by SparkSQLDriver. it runs on hive api.
user can not change reduce number by setting spark.sql.shuffle.partitions

but i think setting hive properties seems just a role to spark sql.

Author: guowei <guowei@upyoo.com>

Closes #1904 from guowei2/temp-branch and squashes the following commits:

7d47dde [guowei] fixed: setting properties like spark.sql.shuffle.partitions does not effective
SPARK-3020: Print completed indices rather than tasks in web UI

Author: Patrick Wendell <pwendell@gmail.com>

Closes #1933 from pwendell/speculation and squashes the following commits:

33a3473 [Patrick Wendell] Use OpenHashSet
8ce2ff0 [Patrick Wendell] SPARK-3020: Print completed indices rather than tasks in web UI