Add some "demos" for collector components

[svrnm]

Feature Request

The current collector configuration coming with the demo-webstore is mostly for receiving traces/metrics and exporting them once again.

I think there's some opportunity to easily add some demos of collector features/components, e.g.

• use some processors like attributesprocessor/transformprocessor to add/delete/... attributes, maybe some of the services are exposing sensitive data (like username) and the processor is dropping that data.
• compute/transform some metrics
• use a sampling processor
• receive metrics from redis?
• have a "legacy" service that exports traces/metrics in a different format
• ...

There could be a second otelcol-advanced-config.yml or those settings could be disabled by default.