Add attribution for icons and routing

frontend/app/map/about/about.html

@@ -3,10 +3,22 @@
 	<h3 class="modal-title">About FacilPad</h3>
 </div>
 <div class="modal-body">
-	<h2>Map Styles</h2>
+	<h2>Icons</h2>
+	<ul>
+		<li><a href="https://glyphicons.com/" target="_blank">Glyphicons</a></li>
+		<li><a href="https://zavoloklom.github.io/material-design-iconic-font/index.html" target="_blank">Material Design Iconic Font</a></li>
+		<li><a href="http://fontello.com/" target="_blank">Fontello</a></li>
+	</ul>
+	<h2>Map data</h2>
 	<dl class="dl-horizontal">
 		<dt ng-repeat-start="layer in layers.base.concat(layers.overlay)" ng-if="layer.attribution">{{layer.name}}</dt>
 		<dd ng-repeat-end ng-bind-html="layer.attribution" ng-if="layer.attribution"></dd>
+
+		<dt>Search</dt>
+		<dd><a href="https://nominatim.openstreetmap.org/" target="_blank">Nominatim</a> / <a href="http://www.openstreetmap.org/copyright" target="_blank">OSM Contributors</a></dd>
+
+		<dt>Directions</dt>
+		<dd><a href="https://www.mapbox.com/api-documentation/#directions">Mapbox Directions API</a> / <a href="http://www.openstreetmap.org/copyright" target="_blank">OSM Contributors</a></dd>
 	</dl>
 </div>
 <div class="modal-footer">