Collab Integration

[Stuffy McStuffins]

I won't take credit for this, though I honestly don't remember who said it; either way, I think I've added a bit more to it.

Basically, an option for the shared editing of a song; improved collab-ing.

It would, honestly, probably not be far too hard to implement, nor code in the first place.  Basically, a link to share the editing rights of a song.  This link would have a randomly generated URL to avoid "griefing" and be something that can just as quickly be turned off.

Some more advanced features that I think would be just as nice for this:

• A note or measure based commenting/suggestion system; an option for whoever has the link to make a comment on a part of a sequence for the collaborators to see.  Along with this, perhaps a ghost-suggestion system, where instead of directly removing or adding notes, such actions can be made as "suggestions".  Along with that could be playing the song based on someone's suggestions.
  
• A dedicated collab mode; so you can decide whether to see the comments, suggestions, etc.
  
• A "Save-History" for every song; having it so that prior saves can be seen and reverted to.  Would help song management and fix painful saved mistakes.  Not to mention, save songs from griefing.
  
• Editors shown at the top; those who contributed to the song could be shown at the top, perhaps separately.  Owner of said sequence can decide who's shown at the top.
  

So yea.  I think the basic feature of having a shared sequence would be the easiest thing to implement here.  Perhaps the other things would take some work, certainly a good amount of GUI work, but I also think some would just be good features to have as a whole.  Would be useful for more than just collabing, anyway.