JavaScript API - UUID

#118.

`v1` method added. One of `node-uuid` is referred to for it.

API is like below:

```javascript
uuid.v1([options]);
```

`options` is quite similar to one of `node-uuid`, except for the `node` property, like below:

`options` - (Object) Optional uuid state to apply. Properties may include:
* `node` - (Number) Node id as 6 bytes number. Default: Randomly generated ID.
* `clockseq` - (Number between 0 - 0x3fff) RFC clock sequence. Default: An internally maintained clockseq is used.
* `msecs` - (Number) Time in milliseconds since unix Epoch. Default: The current time is used.
* `nsecs` - (Number between 0-9999) additional time, in 100-nanosecond units. Ignored if msecs is unspecified. Default: The current time is used.

I think implementing `v1` is quite enough for the UUID module now as we already have `parse` and can get information from each UUID with it.