Changed target directory for the expression parsing tests.
Modified AbstractCodeParser to have the option to log unhandled elements instead of throwing an exception.
Modified child & expression to ignore null children instead of throwing ArgumentNullException.
Re-implemented merging and loading in the DataRepository.
Add a DataRepositoryStatistics class to collect error and logging information from a DataRepository.
Added a new set of RealWorldTests that uses NUnit parameterized test cases.