Stable insertion ordering

[Kilenaitor]

Right now, when the script runs, any discovered unprocessed entries from the wiki will be inserted at position 0, pushing the rest of the playlist down below it. This is with the intent of keeping the newest music at the top of the playlist.

However, these links don't all become available at the same time. So, instead, it's a good idea to keep track of what position the songs should be in the playlist. Should be pretty easy to figure out, but might be more computationally-expensive.

Rough calculation should be:

offset = 0
for each release in front of the one to add:
offset += release * tracks on release

then use that offset as the 'position' argument for insertions.

OTHER option that's potentially much cheaper... is if we detect a new release in the middle... just clear out the playlist and rebuild it lol.

This is potentially more disruptive, though.