Logging all errors in a central location

See: https://groups.google.com/d/topic/glidelibrary/auMdMEA7pw4/discussion

``` java
return new Picasso.Builder(app)
.listener(new Picasso.Listener() {
@Override
public void onImageLoadFailed(Picasso picasso, Uri uri, Exception e) {
Log.e(e, "Failed to load image: %s", uri);
}
})
.build();
```

I'm trying to replace the above block of picasso code. Picasso has a single location where we can listen for and log all errors, whereas Glide requires use to listen every place we request an image. Enhancement request is to build a hook into glide where we can log all requests in a single place such as in the Builder or during configuration.