8271356: JDB: GDB-style command repetition and list auto-advance

[jakobcornell]

This has been under discussion on and off for the past month or so on serviceability-dev, and I think a CSR request is required, so this may be a work in progress.

Notes on the patch:

• The list command previously marked a line in each listing with =>. In a bare list this is the next line up for execution. Previously when requesting a specific location (e.g. list 5) the requested line would be marked. With the patch applied, list will only ever mark the next line up for execution. This is consistent with the behavior of GDB and PDB (at least).
• EOF is printed when the repeat setting is on and a bare list command follows a listing containing the last source line. This feature is from PDB; it's a somewhat softer message than the one for an explicit list request that's out of range.
• I don't speak Chinese or Japanese, so I've omitted localizations for the new messages in those locales. However, I updated the help text in both to include the new commands, with the descriptions left empty for now.

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Progress

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Integration blocker

 ⚠️ Title mismatch between PR and JBS for issue JDK-8271356

Issue

• JDK-8271356: Modify jdb to treat an empty command as a repeat of the previous command ⚠️ Title mismatch between PR and JBS.

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