Added getter for principal in ClientIdentification
Non-functional updates: white space and unused import
Fixes #140: CRUDOperationContext#getOutputDocumentsWithoutErrors no longer includes null output documents
Merge pull request #132 from jewzaam/issue-131

Added getter for principal in ClientIdentification and fixing #140
Added 'who' to HookDoc and set it from OperationContext in HookManager
Merge pull request #141 from jewzaam/add-who-to-hookdoc

Added 'who' to HookDoc and set it from OperationContext in HookManager