Fix some problems reported by Matthias

README.md

@@ -27,3 +27,36 @@ pip install --pre -e .
 jupyter notebook
 ```
 
+## Working on the frontend
+The Notebook frontend depends on a wide set of libraries and package managers.
+NPM is used to macro manage the frontend build process.  You can build the 
+frontend Javascript and LESS by running
+
+```
+npm run build
+```
+
+If you need to build the Javascript alone
+
+```
+npm run build:js
+```
+
+Or LESS
+
+```
+npm run build:css
+```
+
+To build specific sub components, separate using a colon.  i.e. to build only
+the terminal's Javascript
+
+```
+npm run build:js:terminal
+```
+
+To clean all built output
+
+```
+npm run clean
+```

notebook/amd.js

@@ -17,14 +17,19 @@ glob(path.join(source, "**/*.js"), function(err, files) {
                 if (err) {
                     console.error('Could not read file ' + file, err);
                 } else {
-                    mkdirp(path.dirname(toFile), function(err) { if (err) {console.error('Could not mkdirp ', err);} });
+                    mkdirp(path.dirname(toFile), function(err) { 
-                    fs.writeFile(toFile, amdWrap(data), function(err) {
+                        if (err) {
-                        if(err) {
+                            console.error('Could not mkdirp ', err);
-                            return console.error('Could not write file ' + toFile, err);
+                        } else {
-                        }
+                            fs.writeFile(toFile, amdWrap(data), function(err) {
+                                if(err) {
+                                    return console.error('Could not write file ' + toFile, err);
+                                }
+                            });
+                        } 
                     }); 
                 }
             });
         });
     }
-});
+});

package.json

@@ -35,6 +35,7 @@
     "browserify": "^11.0.1",
     "codemirror": "~5.5",
     "concurrently": "^0.1.1",
+    "glob": "^5.0.14",
     "jquery": "^2.0",
     "jquery-ui": "~1.10",
     "less": "~2",