Pipeline monitoring metrics [WIP Draft]

[jmacd]

Part of #83

Replaces #184.

See related research:
open-telemetry/oteps#238

Changes

Describes four new metrics (3 collector, 1 SDK):

• otelcol.receiver.items
• otelcol.processor.items
• otelcol.exporter.items
• otelsdk.producer.items

and five new standard attributes:

• otel.signal
• otel.success
• otel.outcome
• otel.name
• otel.pipeline

[jmacd]

Feedback from semconv meeting:

• Write the descriptive text, add in references to the yaml anchors--then generate will do the right thing.
• Look at error.type attribute value space, it may be incorporated.

[github-actions]

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[github-actions]

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