#172: Added new General Utilities > Select Dependent element(s) option (to complement the Select Depends On option added in v2.1.c). This can be useful when transferring traceability to requirement or state machine diagrams
#173: You now get an information rather than warning dialog when you copy an attribute from a different block and switch it from a publish to subscribe (or vice versa).
#174-#176: Added option to create a flow-port at the same time as creating a traced attribute, plus improved working to copy traceability and highlight port in the browser when it creates one
#177: Added General.Model.ReferenceUnitPath = Relative property to config.Properties so it's set in new models when they're created
