returns the number format applied to the value of a cell
|cell||string||the id of a cell|
|string||the format applied to the value of a cell|
var format = spreadsheet.getFormat("A1"); // ->"currency"
Starting with v4.1, the reference to a cell can be specified in the following format:
var cellFormat = spreadsheet.getFormat("sheet1!A2"); //-> "number"
where sheet1 is the name of the tab.
In case the name of the tab isn't specified, the method will return the format applied to the value of a cell from the tab that is currently active.