Bug 20548: Remove copyright clearance for staff

Bug 20548: Remove copyright clearance for staff

This patch removes the erroneously added workflow that requires staff
users to agree to the copyright clearance declaration defined in the
ILLModuleCopyrightClearance preference. Only OPAC users should be
required to accept the declaration.

To test:
1) Ensure you have at least one ILL backend available:
  https://wiki.koha-community.org/wiki/ILL_backends
2) Ensure you have the "ILLModule" preference enabled
3) Add some text to the "ILLModuleCopyrightClearance" preference
4) As an OPAC user make an ILL request:
  a) Navigate to a search results page in the catalog
  b) Click the "Make an Interlibrary Loan request" link at the bottom
  c) Choose "Create a new request", then select a backend
  d) Observe the text you added earlier is displayed with buttons for
  agreeing or disagreeing
5) As a staff user, select the "ILL requests" button on the front page of
the intranet site
  a) Choose "Create a new request", then select a backend
  b) Observe that you are NOT prompted to agree to the text you added
  earlier

Assigned-to: Andrew Isherwood <andrew.isherwood@ptfs-europe.com>
Signed-off-by: Barry Cannon <bc@interleaf.ie>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Chris Cormack <chrisc@catalyst.net.nz>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>