Extension to Wavelets.jl for Discrete Wavelets

[zengfung]

Hi, my team has developed an extension to your package Wavelets.jl which contains 2D-WPT, stationary transforms, group operations on signals (best basis, denoising, feature extraction). It would be really helpful if you could add a link to our package in your README.md, so that users are aware of these functions and operations in Julia.

The function is still under continuous development, but most of the functions that I've mentioned above are stable. Feel free to check out WaveletsExt.jl and its documentations and let me know if you'd be happy to add WaveletsExt.jl to your link, or if more improvements and developments are needed before you do so. Thanks!

[gummif]

Yes no problem, I will add a reference to the readme.