Update RELEASE_NOTES

Signed-off-by: Leandro Lucarella <[email protected]>

Author: llucax

RELEASE_NOTES.md

@@ -9,9 +9,12 @@ https://frequenz-floss.github.io/frequenz-sdk-python/
 For now the documentation is pretty scarce but we will be improving it with
 time.
 
-## Upgrading
+The most prominent changes in this release is the cleanup of the public API,
+which is much more concise and clear now and the addition of classes
+implementing the new data flow design, in particular the `DataSourcingActor`
+and the `ComponentMetricsResamplingActor`.
 
-<!-- Here goes notes on how to upgrade from previous versions, including deprecations and what they should be replaced with -->
+## Upgrading
 
 * `EVChargerData`'s `active_power_consumption` has been renamed to `active_power`
 
@@ -27,14 +30,62 @@ time.
   changes](https://github.com/frequenz-floss/frequenz-channels-python/blob/v0.11.0/RELEASE_NOTES.md#upgrading-breaking-changes)
   you should be aware of.
 
-## New Features
+* The public API has been cleaned up, several symbols were moved or exposed in
+  a single module, and some symbols were hidden because they are either
+  schedule for deprecation or not yet stabilized.
+
+  * `frequenz.sdk.actor`: The `decorator` sub-module was hidden and now the
+    `@actor` decorator is exposed directly only in the main module.
+
+  * `frequenz.sdk.configs`: was renamed to `frequenz.sdk.config`, `Config` is
+    only exposed in the main module and the `ConfigManager` was moved to
+    `frequenz.sdk.actor.ConfigManagingActor`.
+
+  * The modules `frequenz.sdk.data_handling` and `frequenz.sdk.data_ingestion`
+    were hidden from the public interface and will probably be removed in the
+    future. They are still available as `frequenz.sdk._data_handling` and
+    `frequenz.sdk._data_ingestion` for users still needing them.
+
+  * The module `frequenz.sdk.power_distribution` was renamed to
+    `frequenz.sdk.power` and the `PowerDistributor` was moved to
+    `frequenz.sdk.actor.power_distributing.PowerDistributingActor` (with the
+    utility classes `Request` and `Result`).
+
+  * The module `frequenz.sdk.microgrid` was simplified.
+
+    * All component-related symbols (`.component`, `.component_data`,
+      `.component_states`) were moved to the sub-module
+      `frequenz.sdk.microgrid.component`.
 
-<!-- Here goes the main new features and examples or instructions on how to use them -->
+    * All API client-related symbols (`.client`, `.connection`, `.retry`) were
+      moved to the sub-module `frequenz.sdk.microgrid.client`.
+
+    * The `ComponentGraph` is exposed directly in the main module (and only
+      there).
+
+    * The `microgrid_api` module is now exposed via the main module directly
+      (and thus indirectly renamed to `microgrid`, so instead of using `from
+      frequenz.sdk.microgrid import microgrid_api; microgrid_api.initialize()`
+      (for example) you should use `from frequenz.sdk.microgrid import
+      microgridi; microgrid.initialize()`.
+
+    * The `MicrogridApi` class was renamed to `Microgrid` to make it clear it
+      is not exclusively about the API.
+
+    * The `Microgrid.microgrid_api_client` attribute was renamed to
+      `Microgrid.api_client` to avoid the redundancy.
+
+## New Features
 
 * `MeterData` objects now expose the AC `frequency` measured by the meter.
+
 * `BatteryData` objects now expose the temperature of the hottest block in the
   battery as `temperature_max`
 
-## Bug Fixes
+* A new `frequenz.sdk.actor.DataSourcingActor` was added.
+
+* A new `frequenz.sdk.actor.ComponentMetricsResamplingActor` was added.
+
+* A new `frequenz.sdk.actor.ChannelRegistry` was added.
 
-<!-- Here goes notable bug fixes that are worth a special mention or explanation -->
+* A new module `frequenz.sdk.timeseries` was added.