Add Mercury::Image Controller for Image Handling
user
```ruby
class Mercury::ImagesController < MercuryController
  respond_to :json

  # POST /images.json
  def create
    @image = Mercury::Image.new(params[:image])
    @image.save

    respond_with @image
  end

  # DELETE /images/1.json
  def destroy
    @image = Mercury::Image.find(params[:id])
    @image.destroy

    respond_with @image
  end
end
```
assistant