Fix typo
Merge pull request #18 from pangratz/patch-1

Fix typo
Move to Elasticsearch 0.21.0.Beta1
Due to refactoring in 0.21.x we have to update this plugin
Closes #23.
Add documentation about `ignore_attachments` option
update to 0.90
Replace deprecated method:

```
Closeables.closeQuietly(is);
```

by
 ```
Closeables.close(is, true);
```

Closes #28.
prepare release elasticsearch-river-couchdb-1.2.0
prepare for next development iteration
Create CONTRIBUTING.md
Support for changing id via script
I know two ways to change id.

1. The simply way:

 ```
 "script": "ctx.id = ctx.doc._id = ctx.doc.new_id;"
 ```

2. Associate the _id mapping with a path:

 ```
 {
     "mappings": {
         "my_type": {
             "_id": {"path": "new_id"},
         }
     }
 }
 ```

 and set id to null:
 ```
 "script": "ctx.id = ctx.doc._id = null;"
 ```

But in both cases a river doesn't change id keeping it always as the couchdb's id.

Closes #33.