Rename opentelemetry-ext-otcollector to opentelemetry-ext-opencensus

[owais]

I was trying some example apps locally and was surprised that otcollector exporter uses opencensus internally instead of otlp. I realize now that the plan was to implement opencensus temporarily and eventually migrate to opentelemetry. That makes sense but I think this package should just be renamed to opentelemetry-ext-opencensus as it actually implements an exporter that speaks the OpenCensus protocol. It is not specifically built to export only to OT collector.

Even if we completely drop support for the OpenCensus protocol when we add support for OTLP, I think it should not happen in the same package but in a new package called opentelemetry-ext-otlp instead. This is because OTLP is an open protocol that anyone can implement. opentelemetry-python can export to any service that accepts OTLP, not just the OpenTelemetry collector.

[nirsky]

Is there any plan for implementing the otlp exporter?