Refactor RateLimiter so that if Redis is not running, everything still runs normally (minus the rate limiting protection). My assumption that creating a Redis connection would throw an exception if Redis wasn't running was wrong. The exceptions actually occur when you issue a command. This is for #224.

{% extends "admin/change_list.html" %}
{% block object-tools %}
{% if has_add_permission %}
<ul class="object-tools"><li><a href="add/{% if is_popup %}?_popup=1{% endif %}" class="addlink">Add {{ name }}</a></li>
<li><a href="google_sync/">Google Sync</a></li>
</ul>
{% endif %}
{% endblock %}