[Do Not Merge][POC] Calcite integration

[LantaoJin]

Description

This is the POC of Calcite integration: Leverage the current PPL ANTLR grammar and existing AST and convert the AST to Calcite logical plan (RelNode):

• support basic commands: source, filter, sort, fields, where
• support aggregate functions in stats
• support built-in functions: math, string, datetime
• support join and lookup
• support subquery
• support window functions
• support UDF andJSON functions
• support nested fields: index.b.c
• support executing via Calcite Enumerable/Linq4j
• support executing via ES adaptor
• support converting back Rel to Spark SQL
• support customized optimizer rules

Related Issues

List any issues this PR will resolve, e.g. Resolves [...].

Check List

• Updated documentation (docs/ppl-lang/README.md)
• Implemented unit tests
• Implemented tests for combination with other commands
• New added source code should include a copyright header
• Commits are signed per the DCO using --signoff

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.
For more information on following Developer Certificate of Origin and signing off your commits, please check here.

[LantaoJin]

CI failed with ArrayIndexOutOfBoundsException due to the bug of Calcite 1.36.0+, reported in sbt/sbt-assembly#475

[YANG-DB]

@LantaoJin looks great !!!