Make buildList an object, not an array
Move file handling out of builder.
Test for ‘usedDefine’, recursive requires.
bldr function requires a key.

```
var bldr = require(‘bldr’)(‘mypackage’, __filename);
```

If bldr is used for a dependent package, the usages would conflict.
By adding the key to the bldr function, we can separate usages
in a simple fashion.
builder takes the build data as argument. Add tests.
`bldr` is an exported executable.
Use spec runner by default.
Update `bldr` to pass in data object to builder.
Update example
Separate global define from exports/module definition.
Better variable name s/exists/alreadyAdded/
Add builder test for define usage and dev shim.
Fix AMD wrapper.
Fix stdout ouptut
Make appList an object instead of an array
Store options with appList
bldr.setTransform — add a transform filter function

```
var reactTools = require('react-tools');
bldr.setTransform('jsx', function(src, options) {
  return reactTools.transform(src, {});
});
```
Add ability to add sources to either dev or production.
Send all of info into loadScript
Add `bldr.installExpress`:

This will install a handler on an express app, which
adds a route to serve up all sources in dev mode, as
well as overriding the js app file to serve up the
contents of the dev shim.

```
if (process.env.NODE_ENV !== 'production') {
  bldr.installExpress(server, {rootDir: __dirname, app: '/js/app.min.js'});
}
```