wip: add documentation about the TA CRD

Author: swiatekm

README.md

@@ -600,6 +600,8 @@ For more information about multi-instrumentation feature capabilities please see
 
 ### Target Allocator
 
+TODO: Add information about TargetAllocator CRD
+
 The OpenTelemetry Operator comes with an optional component, the [Target Allocator](/cmd/otel-allocator/README.md) (TA). When creating an OpenTelemetryCollector Custom Resource (CR) and setting the TA as enabled, the Operator will create a new deployment and service to serve specific `http_sd_config` directives for each Collector pod as part of that CR. It will also rewrite the Prometheus receiver configuration in the CR, so that it uses the deployed target allocator. The following example shows how to get started with the Target Allocator:
 
 ```yaml

cmd/otel-allocator/README.md

@@ -86,6 +86,9 @@ The easiest way to do this is to grab a copy of the individual [`PodMonitor`](ht
 > ✨ For more information on configuring the `PodMonitor` and `ServiceMonitor`, check out the [PodMonitor API](https://github.com/prometheus-operator/prometheus-operator/blob/main/Documentation/api.md#monitoring.coreos.com/v1.PodMonitor) and the [ServiceMonitor API](https://github.com/prometheus-operator/prometheus-operator/blob/main/Documentation/api.md#monitoring.coreos.com/v1.ServiceMonitor).
 
 # Usage
+
+TODO: Add information about TargetAllocator CRD
+
 The `spec.targetAllocator:` controls the TargetAllocator general properties. Full API spec can be found here: [api.md#opentelemetrycollectorspectargetallocator](../../docs/api.md#opentelemetrycollectorspectargetallocator)
 
 A basic example that deploys.

docs/crd-changelog.md

@@ -3,6 +3,10 @@
 This document explains major changes made in new CRD versions. It is intended to help users migrate and take
 advantage of the new features.
 
+## TargetAllocator.opentelemetry.io/v1alpha1
+
+TODO
+
 ## OpenTelemetryCollector.opentelemetry.io/v1beta1 
 
 ### Migration