Location for client-space singletons

Right now we hang client-space singletons like `admin` or `user` off of the `Bones` object - only client-side. Typically, a code like the snippet below is executed client-side to set up a global object, modules like `bones-document` would then rely on it.

```
$(function() {
Bones.start();
Bones.initialize(function(models, views, controllers, templates) {
Bones.user = new models['User']();
Bones.user.status();
// ...
```
## Two problems:

1) This pattern cannot be replicated on the server as such global objects would be in the global application scope, not in the client (= window) scope.
2) Having a global object X set up to make a module work as expected is not ideal, we should review better patterns (passing a user/admin/whatever object into constructors?)

Right now we're making hesitant use of the existing pattern described initially. If we solve this issue, we could make much safer assumptions around client space singletons and push more code into modules like `bones-auth` and `bones-document` = reuse more code.
## Potential solutions

Bones could provide a 'request' object that would hang off an Express request server side and the `window` object client side. This 'request' object (better name?) would provide a safe space for client space objects.

More thoughts needed.