FIX: Don't use auto sizes for very small images (emoticons)

lib/email/renderer.rb

@@ -15,7 +15,6 @@ module Email
     end
 
     def html
-
       if @message.html_part
         style = Email::Styles.new(@message.html_part.body.to_s)
         style.format_basic

lib/email/styles.rb

@@ -37,8 +37,8 @@ module Email
           img['height'] = 20
         else
           # having no extra style on email images might work best?
-          img['width'] = 'auto'
-          img['height'] = 'auto'
+          img['width'] = 'auto' if img['width'].to_i > 20
+          img['height'] = 'auto' if img['height'].to_i > 20
           add_styles(img, 'max-width:100%;') if img['style'] !~ /max-width/
         end