jQuery 'load' not firing, need to use 'ready' instead

'get_cart' action was never being executed because the jquery 'load'
event would never fire.  This caused the 'loading...' message to remain
on the cart whenever caching is enabled.  The 'load' event was used for
other actions also, these were also changed to use 'ready'
Added missing semi-colon
removed unreferenced variable
changed admin_url call omitting relative
hide loading animation on ajax complete
removed product rating script
allowed for localization of ajax error message
jQuery 'load' not firing, need to use 'ready' instead

'get_cart' action was never being executed because the jquery 'load'
event would never fire.  This caused the 'loading...' message to remain
on the cart whenever caching is enabled.  The 'load' event was used for
other actions also, these were also changed to use 'ready'