Generate a file path from properties on the given object.

**Examples:**

```js
rte(':a/:b:.c', { a: 'aaa', b: 'bbb', c: 'js' });
//=> 'aaa/bbb/c.js'
```

When a `source` file path is passed as the first argument, it will
be parsed and the resulting object will merged with the data
object (properties on the data object take precendence).

```js
rte('a/b/c.html', ':destbase/:basename', { destbase: 'foo' });
//=> 'foo/c.html'
```

@param {String} `src` Optionally pass a source file path to parse.
@param {String} `dest` Template for the destination file path with `:properties` to replace.
@param {Object} `data` Object with values to pass to the dest.
@api public
function rte(src, dest, data) {
  if (typeof dest === 'object') {
    data = dest; dest = src;
  }
  var rte = new Rte(src, data);
  return rte.stringify(dest);
}