Explain stability guarantees for experimental packages (#177)

* Explain stability guarantees for experimental pkgs

* Remove left-over

README.md

@@ -6,10 +6,20 @@ Generated Go code for the OpenTelemetry protobuf data model.
 
 ## Versioning Policy
 
-The autogenerated Go code follows the stability guarantees as defined in
+The auto-generated Go code follows the stability guarantees as defined in
 [maturity
 level](https://github.com/open-telemetry/opentelemetry-proto?tab=readme-ov-file#maturity-level).
-Packages suffixed as `experimental` might not be kept indefinitely.
+
+Versioning of modules in this project will be idiomatic of a Go project using [Go modules](https://github.com/golang/go/wiki/Modules).
+They will use [semantic import versioning](https://github.com/golang/go/wiki/Modules#semantic-import-versioning).
+Meaning modules will comply with [semver 2.0](https://semver.org/spec/v2.0.0.html) with the following exception:
+
+- Packages with an `experimental` suffix do not comply with [semver 2.0](https://semver.org/spec/v2.0.0.html).
+  - Backwards incompatible changes may be introduced to these packages between minor versions.
+  - These packages are intended to be temporary.
+    They will be deprecated and removed when the protobuf definition stabilizes or is removed.
+    If the protobuf definition stabilizes, the package will be replaced with a stable "non-experimental" package.
+    If the protobuf definition is removed, the package will be removed without a replacement.
 
 ## Getting Started