Add NCrunch support

Currently when used with NCrunch the tests fail because [ReflectionDiscoverableCollection](https://github.com/AutoTestNET/AutoTest.ArgumentNullException/blob/v0.5.4/src/AutoTest.ArgumentNullException/Framework/ReflectionDiscoverableCollection.cs) is used to load assemblies from the file system, since NCrunch doesn't copy the files locally the assemblies are not loaded.
