show the word Editoria instead of the pubsweet logo in navbar

app/components/Navigation/Navigation.jsx

@@ -37,7 +37,9 @@ export default class Navigation extends React.Component {
 
         <Navbar.Header>
           <NavbarBrand>
-            <a href='#'><img src='/pubsweet.jpg' alt='pubsweet' /></a>
+            <a href='#'>
+              Editoria
+            </a>
           </NavbarBrand>
         </Navbar.Header>