Add opentelemetry.io docs

[austinlparker]

Per open-telemetry/opentelemetry.io#472, we're mirroring the docs content on the website to each SIG. When a release occurs and these docs are updated, please make an issue or PR mirroring them to their appropriate location in the website repo (https://github.com/open-telemetry/opentelemetry.io/tree/main/content/en/docs/erlang).

[codecov]

Codecov Report

Merging #237 (186552f) into main (2d5dc8a) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main     #237   +/-   ##
=======================================
  Coverage   34.76%   34.76%           
=======================================
  Files          37       37           
  Lines        3052     3052           
=======================================
  Hits         1061     1061           
  Misses       1991     1991           

Flag	Coverage Δ
api	61.11% <ø> (ø)
elixir	18.33% <ø> (ø)
erlang	34.61% <ø> (ø)
exporter	19.48% <ø> (ø)
sdk	77.33% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
apps/opentelemetry/src/otel_batch_processor.erl	66.32% <0.00%> (-1.03%)	⬇️
apps/opentelemetry/src/otel_resource_detector.erl	92.85% <0.00%> (+1.42%)	⬆️

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