add OA variant (#780)

app/views/home/about.html.erb

@@ -214,7 +214,7 @@
         <p>A more detailed analysis of our running costs is available <a href="http://blog.joss.theoj.org/2019/06/cost-models-for-running-an-online-open-journal" target="_blank">on our blog</a>.</p>
 
         <h4>Income</h4>
-        
+
         <p>JOSS has an experimental collaboration with <%= link_to "AAS publishing", "https://blog.joss.theoj.org/2018/12/a-new-collaboration-with-aas-publishing" %> where authors submitting to one of the AAS journals can also publish a companion software paper in JOSS, thereby receviving a review of their software. For this service, JOSS receives a small donation from AAS publishing. In 2019, JOSS received $200 as a result of this collaboration.</p>
 
         <h4>Donate</h4>
@@ -225,7 +225,7 @@
       <div class="generic-content-item" id="content_license">
         <h1>Content Licensing & Open Access</h1>
         <p>
-          <%= setting(:abbreviation) %> is an open access journal. Copyright of <%= setting(:abbreviation) %> papers is
+          <%= setting(:abbreviation) %> is a <a href="https://en.wikipedia.org/wiki/Open_access#Diamond/platinum_OA" target="_blank">diamond/platinum open access</a> journal. Copyright of <%= setting(:abbreviation) %> papers is
           retained by submitting authors and accepted papers are subject to a <a rel="license"
             href="http://creativecommons.org/licenses/by/4.0/">Creative Commons Attribution 4.0 International
             License</a>.</p>