Added HDFS Table Function and Engine for Data Import/Export

Why it matters

This feature enables seamless integration between ClickHouse and Hadoop Distributed File System (HDFS), allowing users to efficiently import data from and export data to HDFS storage. It addresses the need for interoperability with big data ecosystems and simplifies workflows involving HDFS.

How to use it

Users can use the hdfs table function to read data directly from HDFS within queries, or define tables using the HDFS table engine to persist data in HDFS. Configuration requires specifying HDFS paths and relevant connection settings in the table definition or function parameters.