Anki add-on: Update "lookup" Tags

Some facts are expected to change over time - countries choose new leaders, the list of operating Martian rovers increases by one, the top grossing movie of all time is supplanted by a new blockbuster. This add-on allows you to include a " <lookup> " tag with " href " and CSS " selector " attributes. At startup, or when run from the menu, it checks the web. If the content has changed, the add-on updates the note with the new values and resets the schedules of the affected cards. For a silly example, try this note (be sure to paste it into the HTML editor view, not the normal text editor): Front: Is it Friday already? Back: <lookup href=" http://www.isitfridayalready.com/ " selector="#what">Maybe</lookup> Open Anki on Friday and you'll see this card is New and says "Yes"; on Saturday it's New again and says "No" for the rest of the week. Be really careful what you link to - someone could put some malicious script into a web page, such that when this add-on runs, the downloaded content causes some kind of grief.