Fix reference counting

Check whether reference counting is done correctly. This can also be tested to some extend in unit tests.

added reported bug label

changed the description

This issue should also fix the failing unittests related to exception handling.

mentioned in commit e3ca0cb3

mentioned in commit 863e97cf

added in progress and removed ~76 labels

created branch 2-fix-reference-counting

mentioned in commit bf605ff3

mentioned in merge request !4 (merged)

assigned to @frank

closed via commit 1e326a64

closed via commit bf605ff3

closed via merge request !4 (merged)

removed in progress label

mentioned in commit ecbaf94b

mentioned in merge request !5 (merged)

changed milestone to %Version 0.1.0