update maven dependency syntax 

The syntax should be: 

```
<dependency>
    <groupId>com.github.lkoskela</groupId>
    <artifactId>beaninject</artifactId>
    <version>0.9</version>
</dependency>
```

and not like:

```
<dependency>
    <groupId>beaninject</groupId>
    <artifactId>beaninject</artifactId>
    <version>0.6</version>
</dependency>
```
