By default several Wx objects will auto-scroll to the location of an
expand event or similar actions, as if it had been triggered by a human.
This class provides an implementation of a scroll lock for short-lived
sections of fully self-contained code that will be updating the structure
or content of a tree control or other scrolling object.
When created, the lock will create a Wx update locker for speed and flicker
free changes to the object. It will also remember the current scroll
position of the object.
When destroyed, the lock will move the scroll position back to the original
location if it has been changed in the process of an operation and then
release the update lock.
The result is that all operations on the object should occur with the
tree appearing to stay fixed in place.
Note that the lock MUST be short-lived, as it does not integrate with
the rest of Padres locking system. You should already have all the data
needed to change the object prepared and ready to go before you create the