Release 0.7.1

Release 0.7

Upgraded RustFFT to 6.0
Added consistent support for supplying oversized scratch to DCT methods. Instead of checking that the scratch buffer len is exactly the requested len, we now only check that it's greater than or equal to the requested len.
Documented the normalization of all DCT/DST methods.

Upgraded RustFFT to 5.0
Renamed most stucts and traits in the library in order to conform to the Rust API guidelines on acronyms
Refactored all the process() methods to adopt a "in-place with scratch" architecture. This means that, for example, none of the "convert to FFT" algorithms have to allocate scratch space internally, because they now request it from the caller.

Added a blanket impl for the DCTnum trait, making it easier to use arbitrary numeric types.

Merged each DCT2 and DCT3 algorithm into a single struct that implements both both DCT2 and DCT3 traits, and created a "Type2And3" trait to encompass both. They both require the same precomputed data, so we can save memory and setup time by computing both fro mthe same trait.
Also implemented DST2 and DST3 on the Type2And3 trait -- so a single call to "plan_dct2" or "plan_dct3" etc will let you compute a DCT2, DST3, DCT3, DST3 all from the same instance.
DCT Type 4 instances can also compute DST Type 4. They implement the "Type4" trait, which includes both DCT4, and DST4.
Merged MDCT and IMDCT into the same trait
All of the above are breaking changes that will be very relevant to you if you're referring to specific algorithms or writing your own, but if you're just calling "plan_dct4" or etc, not much should be different.
Added a DST1 trait and added naive and FFT implementations
Added DST2, DST3, DST4 traits, and O(nlogn) implementations for each

Removed the pub keyword from some methods on the DCTplanner that should not have been public

All of the DCT#ViaFFT algorithms now allocate a Vec for internal scratch space, rather than using a member variable, allowing them to be immutable.
[Breaking Change] The process method of all DCT traits take &self instead of &mut self
[Breaking Change] Because all DCT instances are now immutable, all DCT instances that depend on other DCT instances take Arc pointers instead of Box pointers
[Breaking Change] Because all DCT instances are now immutable, the DCT planner now creates and stores Arc pointers to DCT instances instead of Box, and has a cache of algorithm instances for each DCT type
Implemented a "split radix" algorithm for DCT2 and DCT3 that processes power-of-two DCTs much faster than converting them to FFTs
Used the split radix alogirthm to derive several hardcoded "butterfly" algorithms for small DCT2 and DCT3 sizes (specifically, sizes 2,4,8,16)
[Breaking Change] Deleted the obsolete DCT4ViaFFT algorithm. For odd sizes, use DCT4ViaFFTOdd instead. For even sizes, use DCT4ViaDCT3. Both are considerably faster and use considerably less memory in all scenarios.
Lots of style improvements

No prior release notes were kept.