Modified DimensionType to uint & added global ostream operator<<
Extended TestValidate tests heavily & corrected checks & other tests
Added new helper, new util function & corrected existing ones
Further extended TestValidation to test _all_ possible check cases
Refactoring of TestValidate to yield more modular structure
Further refactoring of TestValidate to be more oo than ever :)
Using the new oo TestValidate: set file to valid state after tests

This yields a file which can be used via nixcli for 2nd kind of validation meta testing
Small fixes after rebase fun
Changed tagUnitsMatchRefsUnits not to allow missing units from Set dim

Also adapted tests
Merge pull request #303 from balint42/validation

Validation tests & corrections