Added explicit check on javax.inject.Named annotation
1) Instead of explicitly checking for Named, now checked to see if the
annotation itself is annotated with javax.inject.Qualifier, in the same
way that the code already checks for
com.google.inject.BindingAnnotation.
2) Included a much smaller subset of the unit test in
ObjectMapperModuleTest.
3) Removed unnecessary code reformatting.
Merge pull request #3 from cvuijst/master

Added explicit check on javax.inject.Named annotation