Extracting a section of an ELAN transcript (via 'ELAN.extract') occasionally failed in recent versions of pympi-ling, since it sometimes removed parent annotations on time-aligned tiers before the child annotations on reference tiers that pointed to them. This caused 'remove_annotation' to fail when those child annotations were eventually removed. The changes in this branch fix that problem by removing annotations on reference tiers first, then those on time-aligned tiers.
Extracting a section of an ELAN transcript (via 'ELAN.extract') occasionally failed in recent versions of pympi-ling, since it sometimes removed parent annotations on time-aligned tiers before the child annotations on reference tiers that pointed to them. This caused 'remove_annotation' to fail when those child annotations were eventually removed. The changes in this branch fix that problem by removing annotations on reference tiers first, then those on time-aligned tiers.