Auction fine tuned

In today's update I've fine-tuned the auction process and a few other things, including:

• added extra info to the invoices.
  
• get shopify subdomain from shop URL.
  
• disable accept ad link when add is rejected or already accepted.
  
• cleaned up the transactions list + abbreviations
  
• added email to notify advertiser about inserted ad
  
• fine-tuned the auction process
  
• cleaned up the qr code replacement code
  
• advertisers and publishers can now enable/disable certain emails.