Update KendoGridEx.cs

Put Paging functionality before grouping to allow proper results to page
Update KendoGridEx.cs

Correctly sorts groups asc and desc independently of column sorts.
Merge pull request #2 from shady14u/master

Pull request from shady14u:
* Put Paging functionality before grouping to allow proper results to page
* Correctly sorts groups asc and desc independently of column sorts.