Test error conditions.

Fix 412 template to use standard styling that the other 400 templates use.
Update forbidden error to return status code 403 instead of 400.

Signed-off-by: Mike Terzo <mike@terzo.org>

puppetboard/app.py

@@ -121,7 +121,7 @@ def bad_request(e):
 @app.errorhandler(403)
 def forbidden(e):
     envs = environments()
-    return render_template('403.html', envs=envs), 400
+    return render_template('403.html', envs=envs), 403
 
 
 @app.errorhandler(404)

puppetboard/templates/412.html

@@ -1,11 +1,5 @@
 {% extends 'layout.html' %}
-{% block row_fluid %}
-<div class="container" style="margin-bottom:55px;">
-  <div class="row">
-    <div class="span12">
-      <h2>Feature unavailable</h2>
-      <p>You've configured Puppetboard with an API version that does not support this feature.</p>
-    </div>
-  </div>
-</div>
+{% block content %}
+<h1>Feature unavailable</h1>
+<p>You've configured Puppetboard with an API version that does not support this feature.</p>
 {% endblock %}