- BugFix 1872: events without event assignments cannot be (validly) exported for SBML L2. catch a crash that was happening when the event was deleted. Added a warning that the event was not exported. Also allow the event to be exported to L3 (where it is valid to have an event without assignments).
- BugFix 1872: events without event assignments cannot be (validly) exported for SBML L2. catch a crash that was happening when the event was deleted. Added a warning that the event was not exported. Also allow the event to be exported to L3 (where it is valid to have an event without assignments).

jonasfoe/COPASI,jonasfoe/COPASI,copasi/COPASI,jonasfoe/COPASI,jonasfoe/COPASI,copasi/COPASI,copasi/COPASI,copasi/COPASI,copasi/COPASI,jonasfoe/COPASI,copasi/COPASI,jonasfoe/COPASI,jonasfoe/COPASI,jonasfoe/COPASI,jonasfoe/COPASI,copasi/COPASI,copasi/COPASI,copasi/COPASI