[SPARK-15076][SQL] Add ReorderAssociativeOperator optimizer

## What changes were proposed in this pull request?

This issue add a new optimizer `ReorderAssociativeOperator` by taking advantage of integral associative property. Currently, Spark works like the following.

1) Can optimize `1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + a` into `45 + a`.
2) Cannot optimize `a + 1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9`.

This PR can handle Case 2 for **Add/Multiply** expression whose data types are `ByteType`, `ShortType`, `IntegerType`, and `LongType`. The followings are the plan comparison between `before` and `after` this issue.

**Before**
```scala
scala> sql("select a+1+2+3+4+5+6+7+8+9 from (select explode(array(1)) a)").explain
== Physical Plan ==
WholeStageCodegen
:  +- Project [(((((((((a#7 + 1) + 2) + 3) + 4) + 5) + 6) + 7) + 8) + 9) AS (((((((((a + 1) + 2) + 3) + 4) + 5) + 6) + 7) + 8) + 9)#8]
:     +- INPUT
+- Generate explode([1]), false, false, [a#7]
   +- Scan OneRowRelation[]
scala> sql("select a*1*2*3*4*5*6*7*8*9 from (select explode(array(1)) a)").explain
== Physical Plan ==
*Project [(((((((((a#18 * 1) * 2) * 3) * 4) * 5) * 6) * 7) * 8) * 9) AS (((((((((a * 1) * 2) * 3) * 4) * 5) * 6) * 7) * 8) * 9)#19]
+- Generate explode([1]), false, false, [a#18]
   +- Scan OneRowRelation[]
```

**After**
```scala
scala> sql("select a+1+2+3+4+5+6+7+8+9 from (select explode(array(1)) a)").explain
== Physical Plan ==
WholeStageCodegen
:  +- Project [(a#7 + 45) AS (((((((((a + 1) + 2) + 3) + 4) + 5) + 6) + 7) + 8) + 9)#8]
:     +- INPUT
+- Generate explode([1]), false, false, [a#7]
   +- Scan OneRowRelation[]
scala> sql("select a*1*2*3*4*5*6*7*8*9 from (select explode(array(1)) a)").explain
== Physical Plan ==
*Project [(a#18 * 362880) AS (((((((((a * 1) * 2) * 3) * 4) * 5) * 6) * 7) * 8) * 9)#19]
+- Generate explode([1]), false, false, [a#18]
   +- Scan OneRowRelation[]
```

This PR is greatly generalized by cloud-fan 's key ideas; he should be credited for the work he did.

## How was this patch tested?

Pass the Jenkins tests including new testsuite.

Author: Dongjoon Hyun <dongjoon@apache.org>

Closes #12850 from dongjoon-hyun/SPARK-15076.

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