Fix find_or_initialize_by for Rails 4

Started using this to get Google Auth working quickly on a project. `find_or_initialize_by_email` doesn't work in Rails 4.1 so I fixed it so it would. 

Not sure if this is worth merging as it might break projects that are using this (I'd have to test this in Rails 3) and I don't know how many new projects use it. 

@kmcphillips