need to move arch.promisified into promisified

```js
const regedit = require('regedit').promisified
```
but then if promisified arch is needed then one has to require again:
```js
const regedit = require('regedit').arch.promisified
```
This comes more naturally:
```js
const regedit = require('regedit').promisified
await regedit.arch.somemethod()
```
