KFR 5.2.0 is released

This release mainly focuses on DFT performance (which has been increased up to 40% on x86 and x86_64) and bug fixes.

Changed

• The performance of DFT has been increased up to 40% compared to KFR 5 on x86 and x86_64 in single and double precision, inplace and out of place processing.

Added

• KFR_NO_PERF_TESTS define can now disable performance tests
• CMT_CVAL for extracting constexpr-enabled value from cval_t
• fft_algorithm_selection to select FFT algorithm for given FFT size.

Fixed

• Warnings in Clang 10 https://github.com/kfrlib/kfr/issues/198
• std::is_pov is peprecated in C++20 https://github.com/kfrlib/kfr/issues/190
• DFT sizes 0 and 1 were not processed correctly https://github.com/kfrlib/kfr/issues/195
• Internal compiler error in Visual Studio Compiler 19.37 https://github.com/kfrlib/kfr/issues/194
• Goertzel issue https://github.com/kfrlib/kfr/issues/121
• Bug in nearest_real_or_complex https://github.com/kfrlib/kfr/issues/137
• Fixed operators in KFR_STD_COMPLEX mode
• Testo library: typo in epsilon_scope
• Fix ambiguities with std::identity (C++20)
• Force linking in correct order for multi-architecture binaries