Fix changeSetApplier on handling VM graphnodes

1. Use the OriginalAST property to check for redefined statements .
AstID is only used within the core VM execution
2. Fix old testcases with invalid results
3 Add testcase simulating  modification of connections to a CBN
Merge pull request #1611 from junmendoza/newMaster

Fix changeSetApplier on handling VM graphnodes