Update CHANGELOG

CHANGELOG.md

@@ -5,7 +5,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 ## [1.4.0] - Unreleased
 ### Added
 - Utilities to operate on Gymnasium spaces (`Box`, `Discrete`, `MultiDiscrete`, `Tuple` and `Dict`)
-- `parse_device` static method in ML framework configuration for JAX
+- `parse_device` static method in ML framework configuration (used in library components to set up the device)
 - Model instantiator support for different shared model structures in PyTorch
 - Support for other model types than Gaussian and Deterministic in runners
 
@@ -15,7 +15,9 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 - Update model instantiators definitions to process supported fundamental and composite Gymnasium spaces
 - Make flattened tensor storage in memory the default option (revert changed introduced in version 1.3.0)
 - Drop support for PyTorch versions prior to 1.10 (the previous supported version was 1.9)
-- Speed up distribution construction in PyTorch by disabling checking
+- Speed up PyTorch implementation:
+  - Disable argument checking when instantiating distributions
+  - Replace PyTorch's `BatchSampler` by Python slice when sampling data from memory
 
 ### Changed (breaking changes: style)
 - Format code using Black code formatter (it's ugly, yes, but it does its job)