BibCirculation: fix bug blocking library creation

* Fix a bug due to wrong argument washing name, indeed
  req argument name is lib_type, argument name waited was
  type.  (closes #2550)

* Clean user_data acquired from bibcirculation_dblayer by
  removing comma before to pass data to manipulating
  functions. (closes #2551)

* Handle missing arguments in case of place_new_request_stepX
  url by returning the right template to complete arguments.
  (closes #2552)

* Fix an issue forbidding to print 'List of pending hold
  requests'. (closes #2562)

Signed-off-by: Guillaume Lastecoueres <guillaume@tind.io>