Work magic on track save button

**CLICKING SAVE**
If current user == version owner:
* version saves
If current user is not the version owner: 
* version is sporked and site redirects to new version page
If current user is not logged in:
* redirects to login page

**EVENTUALLY**
If current user is not the version owner: 
* version is sporked **with current track edits** and site redirects to new version page
If current user is not logged in:
* version is created with current track edits
* redirects to login page
* after login (or account creation), site redirects to new version page