Usage with input

Currently gotem fails when target is input component. I suggest to change [this line](https://github.com/callmecavs/gotem/blob/master/src/gotem.js#L16)
```javascript
range.selectNodeContents(target)
```
to

```javascript
range.selectNode(target)
```

Or even check if node is an input.

Start at src/gotem.js line 16, where the issue identifies the range selection for the target. Check the input-element case and verify that copying from an input works after the selection behavior is adjusted.

Written by the indexing model from the issue text.