Pagination in File and E-Library tabs made to work with AJAX

**MODIFICATION OF #865 :** 

**Implemented tab wise pagination in File and E-Library GAPP.**

- Pagination.html generic template used for pagination.
- All the cursor objects are paginated and sent as response with pagination info.
- Subsequent pagination request are fulfilled with ajax.
- One method and url is defined for subsequent pagination requests which is used by ajax.

**Feature to be tested after taking this pull:**
- Go to File or E-Library app and look for pagination in each and every tab. (Ex. All files, Documents, Images    ... etc)
- This pagination is tab specific. (i.e. If second page in images is requested then, only cards of images should       change and not the ones in other tab)
- If total no. of objects in any tab is lesser than 24 then pagination would not be shown.
- If pages are less than or equal to 10 then all the pages are shown else short-type of pagination would be shown.

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**MODIFICATIONS:**
- Now each tab is ajax based.
- Rather than getting all the cards of hidden tab, only landing tab's (all-files) is shown with it's all the cards.
- On click of another tab, ajax call is made to populate the tab's cards. (this AJAX happens only for 1st time.)
- Reduces the *File/E-Library* app's landing-page load time.