📚 Advertize ducc0 in web-page and readme.

Author: mdavezac

README.md

@@ -22,6 +22,9 @@ The **SSHT** code provides functionality to perform fast and exact
 spin spherical harmonic transforms based on the sampling theorem on the
 sphere derived in <a href="http://www.jasonmcewen.org/publication/mcewen-fssht/">McEwen & Wiaux (2011)</a>.
 
+**SSHT** can also interface with [ducc0](https://pypi.org/project/ducc0/) and
+*use it as a backend for the forward, inverse and inverse adjoint transforms.
+
 
 ## INSTALLATION
 

docs/index.html

@@ -51,6 +51,8 @@ <h2>News</h2>
 
       <ul>
 
+        <li><strong>July 2021</strong><br />
+          Release of SSHT 1.4.0 (<a href="https://pypi.org/project/ducc0/">ducc0</a>interface)
         <li><strong>February 2021</strong><br />
           Release of SSHT 1.3.7 (<a href="https://conan.io/center/ssht">conan-center</a>release)
         <li><strong>October 2020</strong><br />
@@ -126,6 +128,9 @@ <h2>Description</h2>
         <a href="http://www.jasonmcewen.org/publication/mcewen-fssht/">McEwen & Wiaux (2011)</a>.
       </p>
 
+      <p> <strong>SSHT</strong> can also interface with <a href="https://pypi.org/project/ducc0/">ducc0</a> and
+        use it as a backend for the forward, inverse and inverse adjoint transforms.
+
       <p>
         In some applications adjoint forward and inverse spherical harmonic
         transforms are also required (for example, when solving convex