#866 removed availability reason from template

#866 removed availability reason from template

+ {{ basket_form.reason }}  was being included in the add_to_basket_form_compact.html template - breaking the style of the product list.

Two thoughts

+ Keep it in but instead of displaying the "reason" maybe incorporate a tooltip or popup to display the message.
+ Maybe move it to the detail page - where there is more room.


For now a disabled button "Out of stock" is in it's place.
![screen shot 2013-10-07 at 2 39 43 pm](https://f.cloud.github.com/assets/726265/1278243/4c7c0632-2f04-11e3-84c7-014be7233fc3.png)