Adds the skeletal backend structure for rejection

* Reworks original pre-qualification flow
* Adds rejection form for subsequent front end magic
Move sign in link to HTML partial
Style basic form elements
Remove adviser sign in from the pre-qual partial
Add content to the YML file and the HTML partial
Add style for the rejection_form
Add class names for input, textarea
Merge pull request #24 from moneyadviceservice/prequalify-rejection

Adds the skeletal backend structure for rejection