dcgp: Differentiable Cartesian Genetic Programming made easy.

New A new UDA is introduced to solve symbolic regression problems. Its called moes (Multi-Objective Evolutionary Startegy) and completes the evolutionary approaches in dcgp which can now be selected to be memetic or not and single objective or multi-objective. Changes The underlying computations of the symbolic regression optimizationlroblem (UDP) is now performed by obake using a vectorized type. Speed improvements are observed of orders between x4 and x100 depending on cases. The problem on nans appearing and exceptions being thrown has been solved by guarding against symengine exceptions and by discarding zero columns and rows when inverting hessians for the Newton step of memetic algorithms. BREAKING: the API has been made uniform for the four UDAs: es4cgp, moes4cgp, mes4cgp, momes4cgp as well as the mutation mechanism. Named parameters have thus changed and default values too. The UDA es4cgp is no longer using a thread bfe to compute the loss. This avoids crashes when pythonic, non thread-safe kernels are used. A bfe can still be set by the user (deprecated in python) after the UDA has been instantiated. Documentation has been improved and all tutorials and examples updated to the new API