address class

xmpp and buddycloud addressing is similar. 
## Formats

```
{user:"frank",domain:"supercool.com"}
```

```
frank@supercool.com
```

```
/user/frank@supercool.com/posts
```
## resource

xmpp addresses also can have resources, then it looks like

```
frank@supercool.com/psi
```
## needed

```
var addr=convert(whatever);
console.log(addr.node);
console.log(addr.jid);
```
