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ARROW-17883: [Java] implement immutable table (#14316)

Table is a new immutable tabular data structure based on FieldVectors.

This PR is described in detail in the included README.md file. The original design discussion can be found [here](https://docs.google.com/document/d/1J77irZFWNnSID7vK71z26Nw_Pi99I9Hb9iryno8B03c/edit#heading=h.a1lebwljypq5), if you're interested.

Note to reviewers:
- This is a fairly large change set. Most of the code is in "getters" in the Row class. These methods are fairly well covered by tests, but it would be good to have someone look especially at the complex vector types. 
- The only changes to existing classes were three new export methods added to the Data class. These use the logic for exporting VectorSchemaRoots. 

Lead-authored-by: Larry White <ljw1001@gmail.com>
Co-authored-by: Larry White <lwhite1@users.noreply.github.com>
Signed-off-by: David Li <li.davidm96@gmail.com>