Refactor Remez exchange into structured Julia and reduce allocations - #667

Process completed with exit code 1.

undefined binding 'DSP.Filters.lagrange_interp' in `@docs` block in docs/src/internals.md:4-20 ```@docs DSP.os_fft_complexity DSP.os_prepare_conv DSP.os_conv_block! DSP.os_filter_transform! DSP.Windows.makewindow DSP.Windows.padplot DSP._zeropad DSP._zeropad! DSP._zeropad_keep_offset DSP.Filters._polyprep DSP.Filters.freq_eval DSP.Filters.build_grid DSP.Filters.lagrange_interp DSP.Periodograms.coherence_from_cs! DSP.optimalfftfiltlength ```

undefined binding 'DSP.Filters.build_grid' in `@docs` block in docs/src/internals.md:4-20 ```@docs DSP.os_fft_complexity DSP.os_prepare_conv DSP.os_conv_block! DSP.os_filter_transform! DSP.Windows.makewindow DSP.Windows.padplot DSP._zeropad DSP._zeropad! DSP._zeropad_keep_offset DSP.Filters._polyprep DSP.Filters.freq_eval DSP.Filters.build_grid DSP.Filters.lagrange_interp DSP.Periodograms.coherence_from_cs! DSP.optimalfftfiltlength ```

undefined binding 'DSP.Filters.freq_eval' in `@docs` block in docs/src/internals.md:4-20 ```@docs DSP.os_fft_complexity DSP.os_prepare_conv DSP.os_conv_block! DSP.os_filter_transform! DSP.Windows.makewindow DSP.Windows.padplot DSP._zeropad DSP._zeropad! DSP._zeropad_keep_offset DSP.Filters._polyprep DSP.Filters.freq_eval DSP.Filters.build_grid DSP.Filters.lagrange_interp DSP.Periodograms.coherence_from_cs! DSP.optimalfftfiltlength ```