allow a node's icon to be set dynamically (#1490)

* create a proto type

* Fixed some problems after reviewing

red/runtime/nodes/registry/registry.js

@@ -579,6 +579,25 @@ var defaultIcon = path.resolve(__dirname + '/../../../../public/icons/arrow-in.p
 function nodeIconDir(dir) {
     icon_paths[dir.name] = icon_paths[dir.name] || [];
     icon_paths[dir.name].push(path.resolve(dir.path));
+
+    if (dir.icons) {
+        if (!moduleConfigs[dir.name]) {
+            moduleConfigs[dir.name] = {
+                name: dir.name,
+                nodes: {},
+                icons: []
+            };
+        }
+        var module = moduleConfigs[dir.name];
+        if (module.icons === undefined) {
+            module.icons = [];
+        }
+        dir.icons.forEach(function(icon) {
+            if (module.icons.indexOf(icon) === -1) {
+                module.icons.push(icon);
+            }
+        });
+    }
 }
 
 function getNodeIconPath(module,icon) {
@@ -607,6 +626,20 @@ function getNodeIconPath(module,icon) {
     }
 }
 
+function getNodeIcons() {
+    var iconList = {};
+
+    for (var module in moduleConfigs) {
+        if (moduleConfigs.hasOwnProperty(module)) {
+            if (moduleConfigs[module].icons) {
+                iconList[module] = moduleConfigs[module].icons;
+            }
+        }
+    }
+
+    return iconList;
+}
+
 var registry = module.exports = {
     init: init,
     load: load,
@@ -629,6 +662,7 @@ var registry = module.exports = {
     getModuleInfo: getModuleInfo,
 
     getNodeIconPath: getNodeIconPath,
+    getNodeIcons: getNodeIcons,
     /**
      * Gets all of the node template configs
      * @return all of the node templates in a single string