Remove bill.amount from search because psql doesn't like LOWER() on a numeric
Many bug fixes, see description

- auto-populate merchant and customer on bill and registration
- QR code spacing and link
- search bills failure
- fix generateToken trustAnchor exception
- prettier ul li navigation CSS
- add $http to RegistrationCtrl
- fix update of bill and registration
- make channel and merchant selects required
- fix QR code generation display on bill page
- add initial bill data