Upgrade to Backbone 1.1.0 — Implements #148

As discussed in #148, I had to re-implement attaching the options passed to a View, which got changed in https://github.com/jashkenas/backbone/commit/bc82a4d3704196a5f4a73c2238db38391ea0c92c.

The tests are green, and the basic example apps run as they should, but please have a look at the Backbone.js 1.1.0 changelog to check for any potential other breaking changes.

> 1.1.0 — Oct. 10, 2013 — [Diff](https://github.com/jashkenas/backbone/compare/1.0.0...1.1.0)

> * Made the return values of Collection's `set`, `add`, `remove`, and `reset` more useful. Instead of returning `this`, they now return the changed (added, removed or updated) model or list of models.
* Backbone Views no longer automatically attach options passed to the constructor as `this.options`, but you can do it yourself if you prefer.
* All `"invalid"` events now pass consistent arguments. First the model in question, then the error object, then options.
* You are no longer permitted to change the id of your model during `parse`. Use `idAttribute` instead.
* On the other hand, `parse` is now an excellent place to extract and vivify incoming nested JSON into associated submodels.
* Many tweaks, optimizations and bugfixes relating to Backbone 1.0, including URL overrides, mutation of options, bulk ordering, trailing slashes, edge-case listener leaks, nested model parsing...