fixes #869 - default text editor was displaying 'undefined' when initial value was missing. now showing blank
fixes #869 - default text editor was displaying 'undefined' when initial value was missing. now showing blank

seanlandsman/ag-grid,ceolter/ag-grid,seanlandsman/ag-grid,ceolter/angular-grid,Eurofunk/ag-grid,Eurofunk/ag-grid,killyosaur/ag-grid,ceolter/angular-grid,ua9msn/ag-grid,makinggoodsoftware/ag-grid,killyosaur/ag-grid,seanlandsman/ag-grid,ceolter/ag-grid,ua9msn/ag-grid,killyosaur/ag-grid,makinggoodsoftware/ag-grid