4.7 pde.tools package

Package containing several tools required in py-pde.

`cache`	Functions, classes, and decorators for managing caches.
`config`	Handles configuration variables of the package.
`cuboid`	An n-dimensional, axes-aligned cuboid.
`docstrings`	Methods for automatic transformation of docstrings.
`expressions`	Handling mathematical expressions with sympy.
`ffmpeg`	Functions for interacting with FFmpeg.
`math`	Auxiliary mathematical functions.
`misc`	Miscellaneous python functions.
`modelrunner`	Establishes hooks for the interplay between `pde` and `modelrunner`
`mpi`	Auxiliary functions and variables for dealing with MPI multiprocessing.
`nested_dict`	Provides a nested dictionary that stores hierarchical mappings.
`output`	Python functions for handling output.
`parse_duration`	Parsing time durations from strings.
`plotting`	Tools for plotting and controlling plot output using context managers.
`spectral`	Functions making use of spectral decompositions.
`typing`	Provides support for mypy type checking of the package.