[!!!][TASK] Change transformer interface to use non static methods

Currently the getTargetMappingType and transformByAnnotation are static
method. This patch change this to allow more complex transformer that need
DI.

This change is breaking if you use custom transform class. In this case
you just need to adapt the previously static methods.
Merge pull request #6 from ttreeagency/feature/NonStaticTransformer

[!!!][TASK] Change transformer interface to use non static methods