add spec model, associate
add spec controller
partial admin_products_list
validate spec
Merge pull request #6 from wayne5540/t5337

T5337
edit spec
add button to product show
add simple format to product desc and spec detail
migrate product price and revuse ui
Merge pull request #10 from wayne5540/t5354

T5354
nested form done
cocoon gem
fix t5348