Add supporting evidences when cloning object
requested to merge github/fork/thibauthourlier/hotfix/new_dissociated_copy into Bugfix/store_evidence
Created by: thibauthourlier
The new_dissociated_copy method in Exon and Transcript was not copying the supporting evidence. So the supporting evidences would be lost each time the method is used
This addition may have an impact on the performance of the code as some models will have many supporting evidence. So maybe it is better to have it as a new method