Update rustfft requirement from 3.0.0 to 4.0.0

[dependabot-preview]

Updates the requirements on rustfft to permit the latest version.

Changelog

Sourced from rustfft's changelog.

[4.0.0]

Breaking Changes

• Increased the version of the num-complex dependency to 0.3. This is a breaking change because we have a public dependency on num-complex. See the num-complex changelog for a list of breaking changes in num-complex 0.3.
• Increased the minimum required Rust version from 1.26 to 1.31. This was required by the upgrade to num-complex 0.3.

[3.0.1]

Fixed

• Fixed warnings regarding "dyn trait", and warnings regarding inclusive ranges
• Several documentation improvements

[3.0.0]

Changed

• Reduced the setup time and memory usage of GoodThomasAlgorithm
• Reduced the setup time and memory usage of RadersAlgorithm

Breaking Changes

• Documented the minimum rustsc version. Before, none was specified. now, it's 1.26. Further increases to minimum version will be a breaking change.
• Increased the version of the num-complex dependency to 0.2. This is a breaking change because we have a public dependency on num-complex. See the num-complex changelog for a list of breaking changes in num-complex 0.2

[2.1.0]

Added

• Added a specialized implementation of Good Thomas Algorithm for when both inner FFTs are butterflies. (#33)

Changed

• Documentation typo fixes (#27, #35)
• Increased minimum version of num_traits and num_complex. Notably, Complex is now guaranteed to be repr(C)
• Significantly improved the performance of the Radix4 algorithm (#26)
• Reduced memory usage of prime-sized FFTs (#34)
• Incorporated the Good-Thomas Double Butterfly algorithm into the planner, improving performance for most composite and prime FFTs

[2.0.0]

Added

• Added implementation of Good Thomas algorithm.
• Added implementation of Raders algorithm.
• Added implementation of Radix algorithm for power-of-two lengths.
• Added FFTPlanner to choose the fastest algorithm for a given size.

Changed

• Changed API to take the "signal" as mutable and use it for scratch space.

[1.0.1]

Changed

• Relicensed to dual MIT/Apache-2.0.

[1.0.0]

Added

• Added initial implementation of Cooley-Tukey.

Commits

• See full diff in compare view

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