Add notes and contribution info to readme (#16)

Author: c24t

README.md

@@ -1,4 +1,18 @@
-# opentelemetry-python
+# OpenTelemetry Python
+[![Gitter chat][gitter-image]][gitter-url]
 
+[gitter-image]: https://badges.gitter.im/open-telemetry/opentelemetry-python.svg
+[gitter-url]: https://gitter.im/open-telemetry/opentelemetry-python?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge
 
-Join the chat at Python SIG gitter: [![Join the chat at Python SIG gitter](https://badges.gitter.im/open-telemetry/opentelemetry-python.svg)](https://gitter.im/open-telemetry/opentelemetry-python?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge)
+The Python [OpenTelemetry](https://opentelemetry.io/) client.
+
+## Contributing
+
+The Python special interest group (SIG) meets regularly. See the OpenTelemetry
+[community](https://github.com/open-telemetry/community#python-sdk) repo for
+information on this and other language SIGs.
+
+See the [public meeting
+notes](https://docs.google.com/document/d/1CIMGoIOZ-c3-igzbd6_Pnxx1SjAkjwqoYSUWxPY8XIs/edit)
+for a summary description of past meetings. To request edit access join the
+meeting or get in touch on Gitter.