spelling: clarify what "Destroy old data" means

kallithea/templates/admin/settings/settings_mapping.html

@@ -1,34 +1,34 b''
 ${h.form(url('admin_settings_mapping'), method='post')}
     <div class="form">
         <div class="fields">
             <div class="field">
                 <div class="label label-checkbox">
                     <label for="destroy">${_('Rescan option')}:</label>
                 </div>
                 <div class="checkboxes">
                     <div class="checkbox">
                         ${h.checkbox('destroy',True)}
-                        <label for="destroy">${_('Destroy old data')}</label>
+                        <label for="destroy">${_('Delete records of missing repositories')}</label>
                     </div>
-                    <span class="help-block">${_('Check this option to remove references to repositories that no longer exist in on the filesystem.')}</span>
+                    <span class="help-block">${_('Check this option to remove all comments, pull requests and other records related to repositories that no longer exist in the filesystem.')}</span>
 
                     <div class="checkbox">
                         ${h.checkbox('invalidate',True)}
                         <label for="invalidate"> ${_('Invalidate cache for all repositories')}</label>
                     </div>
                     <span class="help-block">${_('Check this to reload data and clear cache keys for all repositories.')}</span>
 
                     <div class="checkbox">
                         ${h.checkbox('hooks',True)}
                         <label for="hooks"> ${_('Install Git hooks')} </label>
                     </div>
                     <span class="help-block">${_("Verify if Kallithea's Git hooks are installed for each repository. Current hooks will be updated to the latest version.")}</span>
                 </div>
             </div>
 
             <div class="buttons">
             ${h.submit('rescan',_('Rescan Repositories'),class_="btn")}
             </div>
         </div>
     </div>
 ${h.end_form()}