Support adding custom store fronts

Each country will have its own websites and stores and each user has its own preferences. It would be nice to be able to allow users to define custom stores to their accounts.

I understand this is quite complicated to implement because each website has its own mechanism to search and show data but this could be considered only an “Advanced Setting” where the user would have to provide a script to crawl the website for the title provided by dekudeals, parse the results and return the price. Overtime users would be able to share those scripts or even let you have a curated list of them.