Option item_per_page does not work on almost request to fetch a paginated list

[hadimansouri]

In the almost request to fetch a paginated list of items, setting value for number of items per page does not work.
Also in different place of codes and documents different names are introduced for this option (such as _px_count, _px_c, _px_ps).
Example: REST commands to find list of assets, tags or categories in SDP module.

[hadimansouri]

I resolve this issue for SDP module. Other modules should be edited.

[hadimansouri]

My suggestion is improving function 'setFromRequest' to check key '_px_c' in the request and set item_per_page in the paginator.
This solution will resolve all usage of paginator in different modules