Check for valid director API keys

app/eve_api/templates/eve_api/corporation.html

@@ -13,6 +13,7 @@
         <li><b>Member Count:</b> {{ corporation.member_count }}</li>
         <li><b>Known Members:</b> {{ corporation.eveplayercharacter_set.count }}</li>
         {% if view_members %}
+        <li><b>Full Director API Available: {% if corporation.director_api_keys %}<span style="color: green;">Yes</span>{% else %}<span style="color: red;">No</span>{% endif %}</b></li>
         <li><b>Members with API Keys:</b> {{ corporation.api_keys }}</li>
         <li><b>API Coverage:</b> {{ corporation.api_key_coverage|floatformat:2 }}%</li>
         {% endif %}