Added ability to regenerate certificates from Instructor Dashboard

lms/templates/instructor/instructor_dashboard_2/certificates.html

@@ -92,6 +92,25 @@ import json
         %endif
     % endif
 
+    <hr>
+    <p class="start-certificate-regeneration">
+        <h2>${_("Regenerate Certificates")}</h2>
+        <form id="certificate-regenerating-form" method="post" action="${section_data['urls']['start_certificate_regeneration']}">
+            <p id='status-multi-select-tip'>${_('Select one or more certificate statuses below using your mouse and ctrl or command key.')}</p>
+            <select class="multi-select" multiple id="certificate-statuses" name="certificate_statuses" aria-describedby="status-multi-select-tip">
+                %for status in section_data['certificate_statuses']:
+                    <option value="${status['status']}">${status['status'].title() + " ({})".format(status['count'])}</option>
+                %endfor
+            </select>
+            <label for="certificate-statuses">
+                ${_("Select certificate statuses that need regeneration and click Regenerate Certificates button.")}
+            </label>
+
+            <input type="button" id="btn-start-regenerating-certificates" value="${_('Regenerate Certificates')}" data-endpoint="${section_data['urls']['start_certificate_regeneration']}"/>
+        </form>
+        <div class="message certificate-regeneration-status"></div>
+    </div>
+
     <div class="certificate_exception-container">
         <hr>
         <h2> ${_("Certificate Exceptions")} </h2>