Luke displays weird characters for binary payloads [LUCENE-9065]

When payloads are binary, like short int, Luke displays some unreadable characters.

  

Suggestion improvement: display the original byte string.

Another idea is to try to decode the string similarly to Solr's own decoder/encoder of string and numeric values (and show in a separate column).

@mocobeta FYI

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Migrated from [LUCENE-9065](https://issues.apache.org/jira/browse/LUCENE-9065) by Dmitry Kan
Attachments: [Screenshot 2019-11-25 at 15.59.48.png](https://apache.github.io/lucene-jira-archive/attachments/LUCENE-9065/Screenshot%202019-11-25%20at%2015.59.48.png)

Start by reproducing the unreadable-character display in Luke with a binary payload, using the linked screenshot and issue description as the expected behavior reference. Locate the Luke code path that renders payload values; done means binary payloads are shown as their original byte string, with any decoded representation treated as a separate, clearly defined choice.

Written by the indexing model from the issue text.