[UI-Grid] Add missing definitions (#24835)
[UI-Grid] Add missing definitions (#24835)

* Add missing definitions

Add missing optional parameters for addRowHeaderColumn
Add id and fastWatch to IGridInstance
Renamed 'viewport' to correct case 'viewPort'
Change ColumnDef for Edit events to use IColumnDefOf instead (what the api returns). Should probably be done for other methods as well.

* Missing parameters in description

AgentME/DefinitelyTyped,rolandzwaga/DefinitelyTyped,georgemarshall/DefinitelyTyped,AgentME/DefinitelyTyped,magny/DefinitelyTyped,dsebastien/DefinitelyTyped,markogresak/DefinitelyTyped,magny/DefinitelyTyped,borisyankov/DefinitelyTyped,AgentME/DefinitelyTyped,rolandzwaga/DefinitelyTyped,borisyankov/DefinitelyTyped,dsebastien/DefinitelyTyped,georgemarshall/DefinitelyTyped,AgentME/DefinitelyTyped,mcliment/DefinitelyTyped,one-pieces/DefinitelyTyped,georgemarshall/DefinitelyTyped,georgemarshall/DefinitelyTyped