Initial work on EmailCongress.
Fleshed out EmailCongress feature.

Avoid confirmation_code collisions before the validation.
Added bounce email for messages lacking legit recipients.
Added EmailCongressController tests.
Merge branch 'extend-user-model-3' into email_congress
Merged UserProfile work into EmailCongress.

Copy UserProfile <=> EmailCongress::ProfileProxy where appropriate.
Allow users created by EmailCongress to update their password.
Auto-activate users created by EmailCongress.
Allow users update their email address if sending from an alt.
Added no-valid-recipient bounce email.
Associate EmailCongressLetterSeed with a ContactCongressLetter when it is finalized.
Merge branch 'extend-user-model-3' into email_congress
Fixed generic share message for contactable-less letters.
form_for is incompatible with email forms.
Removed extra authenticity_token. Changed complete_profile route.
Converted letter privacy to bootstrap radio buttons.
Convert preformatted letter text to paragraph-oriented HTML.
Increased text size for letters, adjusted width to approximate 66 characters per line.
Added NANP lib and phone validation based on it.
Disallow local numbers in EmailCongress.
Removed title from email congress profile & form.
Allow blank phone number in EmailCongress profile.
Fixed up EmailCongress letter sending.

Infer zip_four.
Set FormageddonLetter.status to 'START'
Send letters through DelayedJob
Added config.action_mailer.default_url_options to development environment.
Created ExpiredEmailSeedJob and assoc. rake task.

Fixes #375
Added unique DB index to confirmation_code field.
Updated EmailCongress tests to work with the new ZipInferrenceService.