docs: add docs with differences from the APM Python agent

Author: xrmx

README.md

@@ -22,6 +22,7 @@ With EDOT Python you have access to all the features of the OpenTelemetry Python
 * [Get started](./docs/get-started.md)
 * [Manual instrumentation](./docs/manual-instrumentation.md)
 * [Configuration](./docs/configure.md)
+* [Migrating from APM Python Agent](./docs/migrate-from-apm.md)
 
 ## Install
 

docs/migrate-from-apm.md

@@ -0,0 +1,57 @@
+<!--
+Goal of this doc:
+The user is able to understand the differences between the APM Python agent and EDOT
+-->
+
+# Get started
+
+This guide will highlight the major differences between APM Python Agent and the Elastic Distribution of OpenTelemetry Python (EDOT Python).
+For an hands-on approach on setting up EDOT Python refer to the [Get started guide](./get-started.md).
+
+## We are a distribution
+
+EDOT Python being a distribution of OpenTelemetry means we should follow standards and can't always drift from that. That does not mean there isn't still space for innovation.
+
+## Bold on autoinstrumentation
+
+We have choosen to be bold on autoinstrumentation - that is instrument your Python application without change the application code - so you can just focus on your code. This is because OpenTelemetry configuration has more options and configuration knobs that may complicate things.
+
+## Bring your own instrumentation
+
+In EDOT Python we decided to not ship all the available instrumentations in order to accomodate environments where installing more packages than requested may be an issue.
+We provide a tool to discover available instrumentations automatically that can be added to your build workflow. See [Get started](https://github.com/elastic/elastic-otel-python/blob/main/docs/get-started.md#install-the-available-instrumentation).
+
+## Limitations
+
+### Central configuration
+
+At the moment we don't have a Central configuration replacement so all the configurations would be static and should be provided to the application with other manners.
+
+### AWS lambda
+
+At the moment we are not building any custom lambda layer for the Python instrumentation. You can refer to the upstream [Lambda Auto-Instrumentation](https://opentelemetry.io/docs/faas/lambda-auto-instrument/).
+
+### Missing instrumentations
+
+Not all instrumentation we have in APM Python Agent have an OpenTelemetry counterpart, we may port them if there is customer request.
+
+At the moment of writing the following libraries are missing an OpenTelemetry instrumentation:
+- aiobotocore
+- aiomysql
+- aiopg
+- aioredis
+- Azure storage and Azure queue
+- Graphene
+- httplib2
+- pylibmc
+- pyodbc
+- pymssql
+- Sanic, though it may be compatible with the ASGI instrumentation
+- zlib
+
+<!-- ✅ What they should do next -->
+## Next steps
+
+* [Get started](./get-started.md) with EDOT Python.
+* Learn how to add [manual instrumentation](./manual-instrumentation.md).
+* Learn more about viewing and interpreting data in the [Observability guide](https://www.elastic.co/guide/en/observability/current/apm.html).