Create the CODEOWNERS file (#3)

* Create the CODEOWNERS file

* Use the OTel .NET team alias

There will be a few persons that are not member of the OTel .NET team, for now those will be added manually.

* CODEOWNERS using team and README with team info

* Update maintainers and approvers per SIG meeting

.github/CODEOWNERS

@@ -0,0 +1,15 @@
+#####################################################
+#
+# List of approvers for OpenTelemetry .NET Instrumentation
+#
+#####################################################
+#
+# Learn about membership in OpenTelemetry community:
+#  https://github.com/open-telemetry/community/blob/master/community-membership.md
+# 
+#
+# Learn about CODEOWNERS file format: 
+#  https://help.github.com/en/articles/about-code-owners
+#
+
+* @open-telemetry/dotnet-instrumentation-approvers

README.md

@@ -1,2 +1,22 @@
 # opentelemetry-dotnet-instrumentation
 .NET instrumentation and auto-instrumentation
+
+### Community Roles
+
+Maintainers ([@open-telemetry/dotnet-instrumentation-maintainers](https://github.com/orgs/open-telemetry/teams/dotnet-instrumentation-maintainers)):
+
+- [Chris Ventura](https://github.com/nrcventura), New Relic
+- [Greg Paperin](https://github.com/macrogreg), Datadog
+- [Lucas Pimentel-Ordyna](https://github.com/lucaspimentel), Datadog
+- [Mikhail Pranovich](https://github.com/Mikhail-msft), Microsoft
+- [Paulo Janotti](https://github.com/pjanotti), Splunk
+
+Approvers ([@open-telemetry/dotnet-instrumentation-approvers](https://github.com/orgs/open-telemetry/teams/dotnet-instrumentation-approvers)):
+
+- [Colin Higgins](https://github.com/colin-higgins), Datadog
+- [Kevin Gosse](https://github.com/kevingosse), Datadog
+- [Mike Goldsmith](https://github.com/MikeGoldsmith), HoneyComb
+- [Tony Redondo](https://github.com/tonyredondo), Datadog
+- [Zach Montoya](https://github.com/zacharycmontoya), Datadog
+
+Learn more about roles in the [community repository](https://github.com/open-telemetry/community/blob/master/community-membership.md).