Rehook failure processor

This pull request fixes the failure processor for DynamoRevitTests. Due to the way that DynamoRevitTests creates Dynamo, the TransactionWrapper's failure delegate was never set, so failures raised by Revit were never handled and presented error dialogues which broke the tests.

@Randy-Ma This fixes something you've noted in the code that you would need to talk to me about :) If you like this change, I'll remove those comments.

@riteshchandawar This fixes the floors and framing sample and probably several others.