0.3

This pull request is pending on the next stable release of Ractive, in particular https://github.com/ractivejs/ractive/pull/1276. As well as a spot of tidying up, it implements support for sourcemaps with `rcu.make()`. Here's a screenshot of a patched version of ractive-load:

![screen shot 2014-09-28 at 22 57 04](https://cloud.githubusercontent.com/assets/1162160/4436848/63beffb8-4784-11e4-9ff7-512638e66295.png)

The next step will be to create an easy way for loaders to create sourcemaps as part of a build step. Haven't totally figured that part out yet.

## Breaking change!

The [spec allows for](https://github.com/ractivejs/component-spec/blob/master/authors.md#script-tags-and-componentexports-optional) multiple `<script>` elements - their contents are concatenated with a `;`. This is unnecessary complexity, which makes generating the mappings harder than it needs to be. So when this PR is merged, the spec will need to be updated.

An additional change is that `rcu.parse()` now returns an object with `scriptStart` and `scriptEnd` properties, indicating the range covered by the contents of the `<script>` tag. In other words:

```js
parsed.script === source.slice( parsed.scriptStart, parsed.scriptEnd ); // true
```

This shouldn't cause anyone any difficulty, though I mention it because it broke rcu's tests. (They're fixed in this PR.)

## Post-merge tasks

* [ ] update spec to disallow multiple `<script>` elements.
* [ ] merge https://github.com/ractivejs/ractive-load/pull/17