removeContent: also remove from dataTargets

lib/gui.js

@@ -13,11 +13,16 @@ function (chroma, Map, Sidebar, Tabs, Container, Meshstats, Linklist,
     var linkScale = chroma.scale(chroma.interpolate.bezier(["green", "yellow", "red"])).domain([1, 5])
     var sidebar
 
+    function dataTargetRemove(d) {
+      dataTargets = dataTargets.filter( function (e) { return d !== e })
+    }
+
     function removeContent() {
       if (!content)
         return
 
       router.removeTarget(content)
+      dataTargetRemove(content)
       content.destroy()
       contentDiv.removeChild(content.div)
       content = null