Poor UI/UX title when accepting sharing invitation for an existing account.

[crspybits]

1. Accept a sharing invite with a new account (e.g., Facebook).
2. Sign out of that account.
3. Accept a sharing invite, to a 2nd album, with the (intended) same account. The sign-in view title says "New Sharing Account". Which it's not.

It's an existing sharing account. But, a new album. I think we have some state information present in the app to tell us if a user has signed in already (to detect an attempt to sign out, and sign in as a different user), we can use that to change the text on this Sign In view.

[crspybits]

And then, when this operation completes (adding a 2nd sharing album), you get the alert: "Success! Created new sharing user! You are now signed in too!"

Clearly, this an existing sharing user-- and the message should be changed to something like:

"Success! You now have a new sharing album!"