Add data-testid to test relevant elements (fixes #244)

Change-Id: Id908e38f01e426543ed98975544204a9a632294d
diff --git a/templates/exception.html.ep b/templates/exception.html.ep
index f85edc6..abff9aa 100644
--- a/templates/exception.html.ep
+++ b/templates/exception.html.ep
@@ -1,6 +1,6 @@
 % my $msg = stash('msg') // stash('exception')->message // '500: Internal Server Error';
 % layout 'main', title => 'KorAP: ' . $msg;
 
-<p class="no-results"><%= $msg  %></p>
+<p class="no-results" data-testid="error-message"><%= $msg  %></p>
 
 % notify('error' => $msg);
diff --git a/templates/failure.html.ep b/templates/failure.html.ep
index e1f6fb3..c644e3a 100644
--- a/templates/failure.html.ep
+++ b/templates/failure.html.ep
@@ -9,5 +9,5 @@
 <p class="no-results"><%= loc('notIssued') %></p>
 
 % if (stash('err_msg')) {
-<p class="no-results"><%== loc(stash('err_msg'),stash('err_msg')) %></p>
+<p class="no-results" data-testid="error-message"><%== loc(stash('err_msg'),stash('err_msg')) %></p>
 % }
diff --git a/templates/not_found.html.ep b/templates/not_found.html.ep
index 8410580..87d649b 100644
--- a/templates/not_found.html.ep
+++ b/templates/not_found.html.ep
@@ -1,6 +1,6 @@
 % my $msg = stash('msg') // loc('notFound');
 % layout 'main', title => 'KorAP: ' . loc('notFound');
 
-<p class="no-results"><%= $msg %></p>
+<p class="no-results" data-testid="error-message"><%= $msg %></p>
 
 % notify('warn' => $msg);
diff --git a/templates/partial/header.html.ep b/templates/partial/header.html.ep
index 966401e..5a2189a 100644
--- a/templates/partial/header.html.ep
+++ b/templates/partial/header.html.ep
@@ -1,5 +1,5 @@
 % content_block 'headerButtonGroup', { position => 50 }, begin
-  <h3 class="nav-link"><a class="link-guided-tour">Tour</a></h3>
+  <h3 class="nav-link"><a class="link-guided-tour" data-testid="tour-start">Tour</a></h3>
 % end
 
 % content_block 'headerButtonGroup', { position => 100 }, begin
@@ -7,7 +7,7 @@
 % end
 
 <nav class="navbar">
-  <%= link_to 'index', class => 'logo', begin %><h1><span><%= title() // loc('korap_desc') %></span><% if (loc('title_addon')) { %><div class="logoaddon"><%= loc('title_addon') %></div><% } %></h1><% end %>
+  <%= link_to 'index', class => 'logo', 'data-testid' => 'home', begin %><h1><span><%= title() // loc('korap_desc') %></span><% if (loc('title_addon')) { %><div class="logoaddon"><%= loc('title_addon') %></div><% } %></h1><% end %>
 
   <div class="navbar-group">
     %= content_block 'headerButtonGroup'