- Split login_buttons.html and login_buttons.js into multiple files
- Specifically, make it easier to reason about the display of loginButtons whether it is in dropdown mode or not
- Split templates into subtemplates to make it easier to read the login button .html files as "tables of contents"
- Introduce Meteor._loginButtonsSession, which makes it easier to access internal session fields for loginButtons
- Unify code that calls the various Meteor.loginWithFoo() functions
Breaking change: rename "configureLoginServicesDialogForFoo" to "configureLoginServiceDialogForFoo" (in packages such as accounts-facebook)
This is an internal function only used by OAuth implementations and the
equivalent, so rename to a more specific name:
Accounts.updateOrCreateUserFromExternalService.
Change the signature to directly take serviceName and serviceData instead of a
nested data structure with a very specific structure. Similarly, change
Accounts.oauth.registerService's handleOauthRequest callback to un-nest the
service data.
Throw errors on misuse (if you try to use it with the "password" or
soon-to-be-introduced "resume" services, or if you don't provide an id).
Avoid doing no-op user updates if there is nothing new in "extra".
