post
https://api.7digital.com/1.2/playlists//tracks//move
Move the specified track {playlisttrackid} from the specified playlist at {playlistId}, to a location dictated by the "pos" parameter of the POST request data.
The "pos" parameter is the playlistTrackId of the track you wish your selected track to appear AFTER. A value of "0" indicates you wish to place the track at the front of the list.
NOTE: Tracks can also be rearranged at the client side and then posted back to the ~/playlists/{playlistId} endpoint, this offers a lightweight way of doing the same thing.

