[WIP] Full Map data type support

[ivanthescientist]

WIP Prototype

[hz-devops-test]

The job Hazelcast-pr-builder of your PR failed. (Hazelcast internal details: build log, artifacts).
Through arcane magic we have determined that the following fragments from the build log may contain information about the problem.

Click to expand the log file

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---------SUMMARY----------
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[ERROR] Failed to execute goal org.apache.maven.plugins:maven-checkstyle-plugin:3.1.1:checkstyle (default) on project hazelcast: An error has occurred in Checkstyle report generation. Failed during checkstyle execution: There are 2 errors reported by Checkstyle 8.38 with /home/jenkins/jenkins_slave/workspace/Hazelcast-pr-builder_3/checkstyle/checkstyle.xml ruleset. -> [Help 1]
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---------ERRORS-----------
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[ERROR] /home/jenkins/jenkins_slave/workspace/Hazelcast-pr-builder_3/hazelcast/src/main/java/com/hazelcast/sql/SqlColumnType.java:85:5: Missing a Javadoc comment. [JavadocVariable]
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[ERROR] /home/jenkins/jenkins_slave/workspace/Hazelcast-pr-builder_3/hazelcast/src/main/java/com/hazelcast/sql/impl/type/converter/Converter.java:91:5: Executable statement count is 21 (max allowed is 20). [ExecutableStatementCount]
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[mmedenjak]

Please label your PRs. I've labeled this one.

[viliam-durina]

Superseded with #20256