Added support for getExtendersIn(namespace)

This takes in a namespace object and returens any extenders in current
or in any parent namespaces. closes #434
Introduced KnownArtifactDependencyResolver

Resolver for commandTypes, readModelTypes and queryTypes. partially
solves issue #430
Typoed the name in dependencyResolvers
test-code sneaked into the csproj file
Support resolving of instances of commands / readModels and queries

closes #430