Fixed ajax price updates

 - The product price was no longer correctly being updated via the ajax
   call. It looks as though the function registration had dropped off.
   Added it back in, and the price update seems to work ok again.
Grid view not working on products page

 - The grid view has stopped working on the products page. The Grid /
   List icon still works fine, but the display is always in list view.
   The logic that determines the display type is now wrapped in a check
   for both 'show_search' and 'show_advanced_search', and in my case
   neither of these has been set. Reverting this code fixed the problem
   for me.
Merge pull request #770 from mightymuke/product_price

Fixed ajax price updates
Merge pull request #771 from mightymuke/gridview

Grid view not working on products page