DeepXDE v1.15.0

Areas of improvement

• Improve FirstDerivative callback arguments
• Backend PyTorch: Fix Apple MPS GPU support
• Backend PyTorch: dde.nn.PFNN allows remerging the subnetworks after splitting
• Backend PyTorch: Support L-LAAF activation function
• Backend JAX: Support learning rate decay

New APIs

• PointSetOperatorBC supports mini batch

Thanks to all the contributors to this release!

@kyouma @bonneted @vl-dud @mickpires @enigne @fperiago @macjohnny @wenggyaoo @pengpeng-xiao @lululxvi