add functions

- add getLimitNum function to get limit items
- add multi_update function to update a set of items at once
add getLimitNum function to get limit lists

- add getLimitNum function to get limit lists
add getLimitNum function to get limit users

- add getLimitNum function to get limit users
add & modify & remove

- modify getAll() to getLimitNum() to get limit items at each page
- add pagination function to both items and lists
- modify show-all-items function --> transfer functions back to '/' but
passing parameters instead to show all items
- modify get-single-rate function --> return 0 or rate.rating
- remove getAll() in some functions --> passing parameters to '/'
instead
- add item.multi_update to add listId to a set of items
-
modify & add

- modify message showing rating status
- add pagination function (two buttons only so far)
add pagination function

- add pagination function