Unlocking of model files when they are opened in a newer version of the program

When model files that were created in a older version are opened in a newer version, the models are translated to the new version and models that were run in the previous version are unlocked which deletes the analysis results. The unlocking is done to ensure that the results are always calculated by the new version to accommodate enhancements and bug fixes and possible changes to the results data structures. To obtain the results, simply rerun the model in the new version.