RotateTextObject(id, angle[, smooth])
id by the specified
angle (in degrees). A positive angle rotates anti-clockwise, a negative
angle rotates clockwise. Optionally, you can choose to enable anti-aliased
interpolation by passing True in the smooth argument.
Note that for vector text objects, RotateTextObject() will always operate on
the untransformed text object. This means that any previous transformations
applied to the text object using RotateTextObject(), TransformTextObject(),
or ScaleTextObject() will be undone when calling
RotateTextObject().