…pairTableCommand`

### What changes were proposed in this pull request?
Rename the execution node `AlterTableRecoverPartitionsCommand` for the commands:
- `MSCK REPAIR TABLE table [{ADD|DROP|SYNC} PARTITIONS]`
- `ALTER TABLE table RECOVER PARTITIONS`

to `RepairTableCommand`.

### Why are the changes needed?
1. After the PR #31499, `ALTER TABLE table RECOVER PARTITIONS` is equal to `MSCK REPAIR TABLE table ADD PARTITIONS`. And mapping of the generic command `MSCK REPAIR TABLE` to the more specific execution node `AlterTableRecoverPartitionsCommand` can confuse devs in the future.
2. `ALTER TABLE table RECOVER PARTITIONS` does not support any options/extensions. So, additional parameters `enableAddPartitions` and `enableDropPartitions` in `AlterTableRecoverPartitionsCommand` confuse as well.

### Does this PR introduce _any_ user-facing change?
No because this is internal API.

### How was this patch tested?
By running the existing test suites:
```
$ build/sbt -Phive-2.3 -Phive-thriftserver "test:testOnly *AlterTableRecoverPartitionsSuite"
$ build/sbt "test:testOnly *AlterTableRecoverPartitionsParserSuite"
$ build/sbt -Phive-2.3 -Phive-thriftserver "test:testOnly *MsckRepairTableSuite"
$ build/sbt "test:testOnly *MsckRepairTableParserSuite"
```

Closes #31635 from MaxGekk/rename-recover-partitions.

Authored-by: Max Gekk <[email protected]>
Signed-off-by: Wenchen Fan <[email protected]>

…TITIONS]`

### What changes were proposed in this pull request?

In the PR, I propose to extend the `MSCK REPAIR TABLE` command, and support new options `{ADD|DROP|SYNC} PARTITIONS`. In particular:

1. Extend the logical node `RepairTable`, and add two new flags `enableAddPartitions` and `enableDropPartitions`.
2. Add similar flags to the v1 execution node `AlterTableRecoverPartitionsCommand`
3. Add new method `dropPartitions()` to `AlterTableRecoverPartitionsCommand` which drops partitions from the catalog if their locations in the file system don't exist.
4. Updated public docs about the `MSCK REPAIR TABLE` command:
<img width="1037" alt="Screenshot 2021-02-16 at 13 46 39" src="https://user-images.githubusercontent.com/1580697/108052607-7446d280-705d-11eb-8e25-7398254787a4.png">

Closes apache#31097

### Why are the changes needed?
- The changes allow to recover tables with removed partitions. The example below portraits the problem:
```sql
spark-sql> create table tbl2 (col int, part int) partitioned by (part);
spark-sql> insert into tbl2 partition (part=1) select 1;
spark-sql> insert into tbl2 partition (part=0) select 0;
spark-sql> show table extended like 'tbl2' partition (part = 0);
default	tbl2	false	Partition Values: [part=0]
Location: file:/Users/maximgekk/proj/apache-spark/spark-warehouse/tbl2/part=0
...
```
Remove the partition (part = 0) from the filesystem:
```
$ rm -rf /Users/maximgekk/proj/apache-spark/spark-warehouse/tbl2/part=0
```
Even after recovering, we cannot query the table:
```sql
spark-sql> msck repair table tbl2;
spark-sql> select * from tbl2;
21/01/08 22:49:13 ERROR SparkSQLDriver: Failed in [select * from tbl2]
org.apache.hadoop.mapred.InvalidInputException: Input path does not exist: file:/Users/maximgekk/proj/apache-spark/spark-warehouse/tbl2/part=0
```

- To have feature parity with Hive: https://cwiki.apache.org/confluence/display/Hive/LanguageManual+DDL#LanguageManualDDL-RecoverPartitions(MSCKREPAIRTABLE)

### Does this PR introduce _any_ user-facing change?
Yes. After the changes, we can query recovered table:
```sql
spark-sql> msck repair table tbl2 sync partitions;
spark-sql> select * from tbl2;
1	1
spark-sql> show partitions tbl2;
part=1
```

### How was this patch tested?
- By running the modified test suite:
```
$ build/sbt -Phive-2.3 -Phive-thriftserver "test:testOnly *MsckRepairTableParserSuite"
$ build/sbt -Phive-2.3 -Phive-thriftserver "test:testOnly *PlanResolutionSuite"
$ build/sbt -Phive-2.3 -Phive-thriftserver "test:testOnly *AlterTableRecoverPartitionsSuite"
$ build/sbt -Phive-2.3 -Phive-thriftserver "test:testOnly *AlterTableRecoverPartitionsParallelSuite"
```
- Added unified v1 and v2 tests for `MSCK REPAIR TABLE`:
```
$ build/sbt -Phive-2.3 -Phive-thriftserver "test:testOnly *MsckRepairTableSuite"
```

Closes apache#31499 from MaxGekk/repair-table-drop-partitions.

Authored-by: Max Gekk <[email protected]>
Signed-off-by: Dongjoon Hyun <[email protected]>