Explodes this MText entity into a sequence of simple text fragments, passing each fragment to the specified function
The prototype of the fragment elaboration is as follows:
int (*OdDbMtextEnum)(OdDbMTextFragment *fragment, void *param)
If ctxt is null, the current OdGiWorldDraw object will be used.
The elaboration function should return 1 to continue, or 0 to terminate the explosion.
Each new line in this MText entity, and each change of text attributes, will start a new fragment.