Update attribution when background layer changes

js/id/id.js

@@ -217,7 +217,7 @@ window.iD = function(container) {
             .attr('class','pad1 fillD about-block link-list')
             .html("<li><a target='_blank' href='http://github.com/systemed/iD'>view code</a></li> " +
                   "<li><a target='_blank' href='http://github.com/systemed/iD/issues'>report a bug</a></li>" +
-                  " <li>imagery <a target='_blank' href='http://opengeodata.org/microsoft-imagery-details'>provided by bing</a></li>");
+                  " <li id='attribution'>imagery <a target='_blank' href='http://opengeodata.org/microsoft-imagery-details'>provided by bing</a></li>");
 
         var contributors = about.append('div')
             .attr('id', 'user-list')

js/id/ui/layerswitcher.js

@@ -3,7 +3,8 @@ iD.layerswitcher = function(map) {
         sources = [{
             name: 'Bing',
             source: iD.BackgroundSource.Bing,
-            description: 'Satellite imagery.'
+            description: 'Satellite imagery.',
+            link: 'http://opengeodata.org/microsoft-imagery-details'
         }, {
             name: 'TIGER 2012',
             source: iD.BackgroundSource.Tiger2012,
@@ -11,11 +12,13 @@ iD.layerswitcher = function(map) {
         }, {
             name: 'OSM',
             source: iD.BackgroundSource.OSM,
-            description: 'The default OpenStreetMap layer.'
+            description: 'The default OpenStreetMap layer.',
+            link: 'http://www.openstreetmap.org/'
         }, {
             name: 'MapBox',
             source: iD.BackgroundSource.MapBox,
-            description: 'Satellite and Aerial Imagery'
+            description: 'Satellite and Aerial Imagery',
+            link: 'http://mapbox.com'
         }, {
             name: 'Custom',
             source: iD.BackgroundSource.Custom,
@@ -92,6 +95,9 @@ iD.layerswitcher = function(map) {
                 .classed('selected', function(d) {
                     return d.source === map.background.source();
                 });
+            d3.select('#attribution a')
+                .attr('href', d.link)
+                .text('provided by ' + d.name);
         }
 
         content