feat(storage): Add influxd inspect verify-wal tool

[adamperlin]

Closes #9768
Also see #10993

Describe your proposed changes here.

Adds verify-wal sub-command to influxd inspect which will check WAL files for corruption. Given a directory, the tool simply attempts to parse all the entries in any WAL files it finds. If a corrupt entry is found, the file is reported to the user. Do we want to update docs on this tool?

Usage: $ influxd inspect verify-wal --data-dir=/my/storage/dir/

• CHANGELOG.md updated with a link to the PR (not the Issue)
• Well-formatted commit messages
• Rebased/mergeable
• Tests pass
• Documentation updated or issue created (provide link to issue/pr)
• Signed CLA (if not already signed)

[benbjohnson]

Do we want to update docs on this tool?

/cc @stevebang

[sanderson]

@benbjohnson influxdata/docs-v2#290

[jacobmarble]

Looks good!