Sets the <code>Cursor</code> of the Tracker. If this cursor is <code>null</code>
then the cursor reverts to the default.
@param newCursor the new <code>Cursor</code> to display
@exception SWTException <ul>
<li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
<li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
</ul>
Sets the <code>Cursor</code> of the Tracker. If this cursor is <code>null</code> then the cursor reverts to the default.
@param newCursor the new <code>Cursor</code> to display
@exception SWTException <ul> <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> </ul>