mapping<S, T>  function 
 
create a new MappingDefinition
S the source type
T the target type
Implementation
MappingDefinition<S,T> mapping<S,T>() {
  return MappingDefinition<S,T>();
}
create a new MappingDefinition
S the source type
T the target type
MappingDefinition<S,T> mapping<S,T>() {
  return MappingDefinition<S,T>();
}