Fixes on DataGrids and new tests

Hello, made some fixes on DataGrids. White always found 0 Cells in DataGrid (first seen while testing wpf app) but with rows cout all was ok. Also added tests on made changes and ran old tests also (they pass). 
I managed to see that WinForms like to have localized values for ControlType and some properties (such as Name property for Cells and Rows). Because of this the finding routine you use for Table can find nothing. And as I saw the localization of Windows itself can make some properties appear as localized while others can change to local language only if VS have local language pack (no matter is it now at the very moment in English or in local).