1. Replaced function call rc_util.update_state with rc_util.certify_account
2. Added callback function for certify_account

Feat account renewal1

See merge request !1

2. Sending to error page of eppa not valid

removed hard-coded value

See merge request rc/self-reg-form!9

added flask-cors and used allow cross_allowed_origins to fix the issue seen on prod cluster (400 CORS error)

made UI changes to the app

See merge request rc/self-reg-form!8

sending text message for welcome message, error message and cancel message as a variable from messages.py