Improve logging and generator output.

[dblock]

Description

• Displays the word "ERROR" or "WARNING" when logging at various levels.
• Adds logger.log that wraps console.log.
• Adds tests for Logger.
• Improves a warning message in the generator to be more useful.
• Adds tests for merge and linter command line tools.

Note that console.error, console.warn and friends are all aliases of console.log, they don't do anything different.

Issues Resolved

Closes #285.

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[github-actions]

Changes Analysis

Commit SHA: d14327c
Comparing To SHA: 3ad078c

API Changes

Summary

NO CHANGES

Report

The full API changes report is available at: https://github.com/opensearch-project/opensearch-api-specification/actions/runs/9405132747/artifacts/1576171242

API Coverage

	Before	After	Δ
Covered (%)	476 (46.62 %)	476 (46.62 %)	0 (0 %)
Uncovered (%)	545 (53.38 %)	545 (53.38 %)	0 (0 %)
Unknown	24	24	0