Copy change to make it easier for visitors to understand that they have not been given their
first choice of a slot.

[Finishes #79610480]
Display only start times of unsuccessful slots
Merge pull request #83 from ministryofjustice/copy-change-around-slots-79610480

Copy change to make it easier for visitors to understand that they have ...
WIP all possible canned responses
Use GOV.UK Elements styles

* block-label
* panel-indent
Change appearance of block labels when interacting
Show details of response conditionally
Added help content to processing form
Tidy layout of processing form
Make GOVUK resources more visible
Fix IE6 block inputs
Add booking calendar to processing form
Processing form update copy and merge visiting allowance
Fix visitor clickable labels
Amend calendar mark-up to centre radio buttons
Accept processing form submission when no fields selected
Add VO reference number to confirmation email