Bug 16400 [Follow-up] Proposal to uniform the placement of submit buttons

Bug 16400 [Follow-up] Proposal to uniform the placement of submit buttons

This follow-up makes some corrections to the markup of the cancel
button:

- Use <a> instead of <button> to eliminate the need for an "onclick"
  attribute.
- Remove the "cancel" class which adds unwanted padding.
- Correct the destination of the cancel button when cancelling during an
  edit (should redirect to the patron detail page).

Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>
Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>