Change Google+ API to Local Auth or Google Identity

[jberns]

https://developers.google.com/identity/

[lrm25]

It's Luke from last Monday. I looked at the issue a bit. Google provides migration instructions here:
https://developers.google.com/identity/sign-in/web/quick-migration-guide

So it looks like the changes required would be:

Local auth:

1. Notify users that they won't be able to use google to sign in anymore, and tell them to use local authentication
2. Remove any google sign-in buttons on the client pages
3. Remove a bunch of dead code

Google Identity:

1. Change the Google+ login buttons to Google Identity ones, as described in the link
2. Replace the OAuth-handling code on H4H's client pages and server with Google's token-handling code

The latter is definitely more work and more learning, but the least annoying to users. I'd go with the latter just because of the lack of inconvenience. What do you think?