updated so that only the current tab gets total

updated popup.html: added new error element to display error if total does not match current tab
background.js: adds tab_id to request object
popup.js: added logic to handle error
content.js: added if statemnt so that if current wishlist is homepage of wishlist not to return anything
	    for the wishlist id.
fixed content script so that it properly excludes wishlist "homepage" id instead of exluding all ids parsed from url