Rename branches with es-x.x where x.x is the ES version

(cherry picked from commit bc68c35)
Update to elasticsearch 1.2

Closes #56.

(cherry picked from commit 7897669)
Default couchdb db name should be river name

When you don't provide any settings for the `couchdb` river, the expected couchdb database is `db`:

```
PUT _river/my_db/_meta
{
    "type" : "couchdb"
}
```

Like when you set any attribute for the `couchdb` river, it should use the river name instead. In the previous example, the database should be `my_db`.

Closes #60.

(cherry picked from commit 5747376)
Use elasticsearch test framework

We want to have real integration tests.

If you set `-Dtests.couchdb`, integration tests will run.

Tests will expect a local `couchdb` service running on `localhost:5984`.

Closes #47.

(cherry picked from commit e777941)
Update to elasticsearch 1.3.0

Closes #57.

(cherry picked from commit ad6cc83)
Update to elasticsearch 1.4.0

Closes #58.

(cherry picked from commit af5e76d)