Please specify a storage - S3

Nobody has claimed this yet.

I'm trying to get the module to work with S3 - however, I keep getting the error:

```
Please specify a storage
```

I've tried both:

```
var imager = new Imager(imagerConfig.variants.item, imagerConfig.storages.amazon);
var imager = new Imager(imagerConfig.storages.amazon);
```

With the config:

```
var config = require("./config");

/**
* Expose
*/

exports.variants = {
item: { // variant
thumb: { // preset
options: { // preset options
pool: 5,
scale: { width: 200, height: 150, type: 'contain' },
crop: { width: 200, height: 150, x: 0, y: 0 },
format: 'png',
rotate: 'auto',
},
rename: function (file, preset) {
return;
// return 'users/1/' + preset + '/' + file.name;
}
},
large: {
original: true // upload original image without image processing
}
}
};

exports.storages = {
local: {
provider: 'local',
path: '/tmp',
mode: 0777
},
amazon: {
provider: 'amazon',
key: config.amazon.secret,
keyId: config.amazon.id,
container: config.amazon.bucket
}
};
```

Start at the Imager constructor and trace how the config.storages.amazon object is validated, using the reported "Please specify a storage" error as the entry point. Determine why the shown S3 configuration is rejected and verify that a supported S3 storage configuration is accepted.

Written by the indexing model from the issue text.