Browser *and* Node.js module import

I have reinstalled `uri-templates` under an alias:

```
jspm install uri-templates=npm:uri-templates
```

And added the corresponding Node module:

```
npm i uri-templates --save
```

And updated the import path from `npm:uri-templates` to `uri-templates`.

This allows the import to work in browsers and Node.js. :-)

Please see breakdown in commits, as most of the diff is because of an update to the jspm CLI.
The idea was that Node users would do an `npm install` instead of `jspm install`, as Node’s `require` of course looks inside `node_modules`, not `jspm_packages`.

As per https://github.com/argo-rest/theseus/issues/1#issuecomment-62278120, I'm going to investigate using SystemJS is Node.js, which would make this fix redundant.