fix #29 : envoyer le lien magique par email (envoyer_mail_smtp)

database/migration_003_profile_slug.sql

@@ -0,0 +1,2 @@
+ALTER TABLE user_profiles ADD COLUMN IF NOT EXISTS profile_slug TEXT NOT NULL DEFAULT '';
+CREATE UNIQUE INDEX IF NOT EXISTS user_profiles_profile_slug_idx ON user_profiles (profile_slug) WHERE profile_slug <> '';