feat: add warning generator for missing deps

addon/__dev__/warnOnMissingDependencies.js

@@ -0,0 +1,25 @@
+'use strict';
+
+var pkg = require('../../package.json');
+
+module.exports = function warnOnMissingDependencies (addon, renderer, deps) {
+    var missing = [];
+
+    for (var i = 0; i < deps.length; i++) {
+        var name = deps[i];
+
+        if (!renderer[name]) {
+            missing.push(name);
+        }
+    }
+
+    if (missing.length) {
+        var str = 'Addon "' + addon + '" is missing the following dependencies:';
+
+        for (var j = 0; j < missing.length; j++) {
+            str += '\n require("' + pkg.name + '/addon/' + missing[j] + '").addon(renderer);';
+        }
+
+        throw new Error(str);
+    }
+};