Document release process for OTEL hotfixes (#191)

* Document how to do hotfixes for OTEL

Signed-off-by: Pavol Loffay <p.loffay@gmail.com>

* Fix

Signed-off-by: Pavol Loffay <p.loffay@gmail.com>

* typos

Signed-off-by: Pavol Loffay <p.loffay@gmail.com>

Author: pavolloffay

OPENTELEMETRY_AGENT_HOTFIXES.md

@@ -0,0 +1,21 @@
+# Hotfixes for OpenTelemetry javaagent
+
+All fixes for the core [open-telemetry/opentelemetry-java-instrumentation](https://github.com/open-telemetry/opentelemetry-java-instrumentation)
+should be submitted to the upstream project. However, merge and release into upstream might take some time
+therefore urgent hotfixes can be submitted to the fork [hypertrace/opentelemetry-java-instrumentation](https://github.com/hypertrace/opentelemetry-java-instrumentation).
+
+Changes to the fork are done in a maintenance branches e.g. `v0.13.x` and locally tested and released.
+The fixed artifacts are published to the [Hypertrace Binray](https://bintray.com/hypertrace/maven).
+Then the released artifacts can be consumed by version(s) change in gradle scripts in this repository.
+
+## Hotfix release of hypertrace/opentelemetry-java-instrumentation
+
+This [commit](https://github.com/hypertrace/opentelemetry-java-instrumentation/commit/88c2b113d0cc2fad01ddde9cccdab3b09cbfb6da)
+shows an example of release configuration for `javaagent` artifact. 
+
+```bash
+git checkout -b v0.13.x
+# make required changes and run tests locally
+git tag 0.13.2-ht # use -ht suffix to denote that this is forked version
+ORG_GRADLE_PROJECT_publishUser=<bintray-user> ORG_GRADLE_PROJECT_publishApiKey=<bintray-api-key> ./gradlew bintrayPublish -Prelease.useLastTag=true
+```