[IMP] web_widget_progressbar_gradient: Add inverse option

Allows to reverse the gradient rendering

web_widget_progressbar_gradient/static/description/index.html

@@ -373,7 +373,14 @@ ul.auto-toc {
 <p>This module allows to display progress bars with colorized gradient bar.
 The color will increase following value from green passing per yellow
 and finishing to red.</p>
+<ul class="simple">
+<li>Normal rendering:</li>
+</ul>
 <p><img alt="Progressbar Gradient" src="https://raw.githubusercontent.com/OCA/web/16.0/web_widget_progressbar_gradient/static/description/progressbar_gradient.png" /></p>
+<ul class="simple">
+<li>Reverse rendering:</li>
+</ul>
+<p><img alt="Progressbar Inverse Gradient" src="https://raw.githubusercontent.com/OCA/web/16.0/web_widget_progressbar_gradient/static/description/progressbar_gradient_inverse.png" /></p>
 <p><strong>Table of contents</strong></p>
 <div class="contents local topic" id="contents">
 <ul class="simple">
@@ -393,6 +400,8 @@ and finishing to red.</p>
 <ul class="simple">
 <li>When declaring a progressbar field, use the ‘progressbar_color’
 widget.</li>
+<li>Add the inverse option to reverse the colors on the progress bar
+field: <tt class="docutils literal"><span class="pre">options=&quot;{'inverse':</span> true}&quot;</tt></li>
 </ul>
 </div>
 <div class="section" id="known-issues-roadmap">
@@ -423,6 +432,7 @@ If you spotted it first, help us to smash it by providing a detailed and welcome
 <ul class="simple">
 <li>Denis Roussel <a class="reference external" href="mailto:denis.roussel&#64;acsone.eu">denis.roussel&#64;acsone.eu</a></li>
 <li>Jacques-Etienne Baudoux <a class="reference external" href="mailto:je&#64;bcim.be">je&#64;bcim.be</a></li>
+<li>Souheil Bejaoui <a class="reference external" href="mailto:souheil.bejaoui&#64;acsone.eu">souheil.bejaoui&#64;acsone.eu</a></li>
 </ul>
 </div>
 <div class="section" id="maintainers">