More tests
Fix write-attribute transformer
add method to kickoff the path transformation
Clean up AttributeTransformationDescriptionBuilder API
Move TransformationRule creation into TransformingDescription
Implement UndefineAtribute transformation
use discard policy
Get rid of ModelTransformer
cleanup description a bit
add operation transformation overrides
Allow for complex RejectAttributeCheckers
NameFromPathConverter
Some javadoc
Rename operations
test attribute <> resource transformations
Split checkers into operation and resource methods and test check external attributes in checkers/converters
Use correct address for readResource() when transforming ops
minor api clarification
use convertAttribute() also to add attributes
rename AbstractTransformationContext