v4.0.0

• Updated to Apache 2.0 license.

• Bumped minimum dev dependency of newrelic (agent) to 6.11 for license matching.

• Updated metric retrieval from agent for assert.metrics to match newer agent versions.

  Breaking: assertions are now only compatible with newrelic (agent) versions 6+.

• Added third party notices file and metadata for dependencies.

• Updated readme with more detail.

• Added issue templates for bugs and enhancements.

• Added code of conduct file.

• Added contributing guide.

• Added pull request template.

• Migrated CI to GitHub Actions.

• Added copyright headers to all source files.

• Added .vscode to .gitignore.

• Added additional items to .npmignore.