[SPARK-17257][SQL] the physical plan of CREATE TABLE or CTAS should take CatalogTable

[cloud-fan]

What changes were proposed in this pull request?

This is kind of a follow-up of #14482 . As we put CatalogTable in the logical plan directly, it makes sense to let physical plans take CatalogTable directly, instead of extracting some fields of CatalogTable in planner and then construct a new CatalogTable in physical plan.

How was this patch tested?

existing tests.

[cloud-fan]

cc @yhuai@gatorsmile@liancheng

[SparkQA]

Test build #64461 has finished for PR 14823 at commit cdd900d.

• This patch fails Spark unit tests.
• This patch merges cleanly.
• This patch adds the following public classes (experimental):
  • case class CreateDataSourceTableCommand(table: CatalogTable, ignoreIfExists: Boolean)

[SparkQA]

Test build #64525 has finished for PR 14823 at commit 0e9b3d2.

• This patch passes all tests.
• This patch merges cleanly.
• This patch adds no public classes.

[gatorsmile]

I missed this ping. Will review it tomorrow.

[gatorsmile]

We can remove https://github.com/cloud-fan/spark/blob/0e9b3d2a81f0251f710eae42adca307cd9c69d33/sql/core/src/main/scala/org/apache/spark/sql/execution/SparkSqlParser.scala#L316-L318 ?

After this PR, it becomes much clear to users. We can support Create External Data Source Table! We just need to confirm the path is provided.

[cloud-fan]

removing this means we change the syntax, I'd like to avoid it in this PR, and that's why I leave this TODO here, we can do it in follow-up

[gatorsmile]

LGTM except one minor comment.

[SparkQA]

Test build #64759 has finished for PR 14823 at commit 00bf25b.

• This patch fails to build.
• This patch merges cleanly.
• This patch adds no public classes.

[SparkQA]

Test build #64762 has finished for PR 14823 at commit 52a40d9.

• This patch passes all tests.
• This patch merges cleanly.
• This patch adds no public classes.

[cloud-fan]

thanks for the review, merging to master!