Version 1.5.3

This release fixes two issues

• When reading string data from the dataset, the strings were implicitly converted to np.str_ data type. They are ensured to be kept as native str now (pr #536)

• When reading data slices with data_array.get_slice method from an event array in SliceMode.Data that did not contain any events, a OutOfBounds exception was thrown. This is now caught and instead an empty DataView is returned.