ViewModelFactory is now located on first use,

ViewModelFactory is
Used GetDependencyResolver() instead of IoCConfiguration.DefaultDependencyResolver

Used GetDependencyResolver() instead of
IoCConfiguration.DefaultDependencyResolver to resolve the
ViewmodelFactory in LogicBase.

IoCConfiguration.DefaultDependencyResolver is only for static context.
Merge pull request #21 from jensweller/develop

ViewModelFactory is now located on first use instead of the static constructor so it can be customized in the ServiceLocator.