PowerDistributing: Add support for n:m relations in invs:bats (#660)

- Allow component graph to be a DAG instead of a tree
- Fix comments in tests
- Don't guess missing power bounds from adjacent components
- GraphGenerator: Add function to generate list of components
- PowerDistributing: Add n:m support for inverters:batteries

refs #501

Author: Marenz

RELEASE_NOTES.md

@@ -32,6 +32,11 @@
 
 
 
+- The PowerDistributingActor now supports n:m relations between inverters and
+  batteries.
+  This means that one or more inverters can be connected to one or more batteries.
+
+
 ## Bug Fixes
 
 - Fix rendering of diagrams in the documentation.

src/frequenz/sdk/actor/power_distributing/_distribution_algorithm/__init__.py

@@ -4,6 +4,7 @@
 """Utilities to manage power in a microgrid."""
 
 from ._distribution_algorithm import (
+    AggregatedBatteryData,
     DistributionAlgorithm,
     DistributionResult,
     InvBatPair,
@@ -13,4 +14,5 @@
     "DistributionAlgorithm",
     "DistributionResult",
     "InvBatPair",
+    "AggregatedBatteryData",
 ]