Implement @ReceiverAction for issue #851

As i got some free time today, i decided to do another contribution to AA. :)

I implemented the @ReceiverAction annotation suggested in https://github.com/excilys/androidannotations/issues/851.

The code is based on the `ServiceActionHandler`.

This class
```java
@EReceiver
public class MyReceiver extends BroadcastReceiver {

	@Override
	public void onReceive(Context context, Intent intent) {

	}

	@ReceiverAction("MyAction")
	public void doSomething() {
		// Your code ...
	}

	@ReceiverAction(DownloadManager.ACTION_DOWNLOAD_COMPLETE)
	public void onDownloadComplete(@ReceiverAction.Extra(DownloadManager.EXTRA_DOWNLOAD_ID) long extraDownloadId) {
		// Your code ...
	}

	@ReceiverAction("anotherAction")
	public void helloWorld(@ReceiverAction.Extra("hello_world") String heyWorldyWorld) {
		// Your code ...
	}
}
``` 

genereates the following code
```java
public final class MyReceiver_
    extends MyReceiver
{

    public final static String ACTION_HELLO_WORLD = "anotherAction";
    private Context context_;
    public final static String HELLO_WORLD_EXTRA = "hello_world";
    public final static String ACTION_ON_DOWNLOAD_COMPLETE = "android.intent.action.DOWNLOAD_COMPLETE";
    public final static String EXTRA_DOWNLOAD_ID_EXTRA = "extra_download_id";
    public final static String ACTION_DO_SOMETHING = "MyAction";

    @Override
    public void onReceive(Context context, Intent intent) {
        context_ = context;
        init_();
        super.onReceive(context, intent);
        String action = intent.getAction();
        if (ACTION_HELLO_WORLD.equals(action)) {
            Bundle extras = intent.getExtras();
            if (extras!= null) {
                String hello_worldExtra = extras.getString(HELLO_WORLD_EXTRA);
                super.helloWorld(hello_worldExtra);
            }
            return ;
        }
        if (ACTION_ON_DOWNLOAD_COMPLETE.equals(action)) {
            Bundle extras = intent.getExtras();
            if (extras!= null) {
                long extra_download_idExtra = extras.getLong(EXTRA_DOWNLOAD_ID_EXTRA);
                super.onDownloadComplete(extra_download_idExtra);
            }
            return ;
        }
        if (ACTION_DO_SOMETHING.equals(action)) {
            super.doSomething();
            return ;
        }
    }

    private void init_() {
    }

}

```
@yDelouis will review your code later, until that i just have on note: i think this is not a functional test. In the functional test project, every annotation should have been tested to see it really does what we think it does. For example in this case we should broadcast an event and check that the annotated methods are indeed called. Also i think we should create another class for these. I know the `@Receiver` annotation by @yDelouis has similar "functional" test. Actually if we just want to be sure that an annotated code compiles, we should write a compile time test in the `androidannotations/src/test` folder.