Bug 7523: Improve checks for routing permissions

Bug 7523: Improve checks for routing permissions

- system preference RoutingSerials and user permission routing
  should be taken into account
- print routing list should be independent from routing permission

To test, compare to master and check:

1) If system preference RoutingSerials is OFF, routing list functionality is
not visible in the templates.

2) If system preference RoutingSerials is ON, but user doesn't have routing
permission, routing list functionality is not visible in templates,
with exception of 'print list' on the serial collection page.

3) If system preference RoutingSerials is ON and user has routing permissions,
all routing links are visible (serial collection, serials navigation,
result list of serial search)

Additional changes:
Changed labels on templates to match HTML4 rule from coding guidelines.
http://wiki.koha-community.org/wiki/Coding_Guidelines#Upper_and_Lower_cases_in_strings

Signed-off-by: Julian Maurice <julian.maurice@biblibre.com>
Signed-off-by: Paul Poulain <paul.poulain@biblibre.com>