modifyshelfcontents-
if this script has to modify the shelve content.
shelfnumber-
to know on which shelve this script has to work.
addbarcode-
op-
op can be equals to:
* modifsave to save change on the shelves
* modif to change the template to allow to modify the shelves.
viewshelf-
to load the template with 'viewshelves param' which allow to read the shelves information.
shelves-
if equals to 1. then call the function shelves which add
or delete a shelf.
addshelf-
if the param shelves = 1 then addshelf must be equals to the name of the shelf to add.