Add select method to shapes

In the current office-js Excel API, there is no select method available for Shapes, nor does the API provide a TopLeftCell property. This means I have to revert to finding the current position of the shape by stepping through the rows and columns of the worksheet until I exceed both the left and top of the shape. A very slow and resource-intensive piece of code.

Please add both the topLeftCell property and the select method to the shape object.