fix(case-sensitivity): ensure new registrations downcase UID if Devise case_insensitive_keys include Email
fix(uid updates): ensure UID is updated alongside Email (accounting for case sensitivity)
use before_save to keep uid in sync with email
Merge pull request #71 from booleanbetrayal/fix_case_insensitive_email_registration

fix(registration and update): Ensure UID is updated alongside Email, and case-sensitivity is honored