Adding generics to custom mappers

Hi,

Here's my input on generics & custom mappers. I tried to cover as many generic type / wild card situations as possible. The main class is the MethodMatcher. It tries to match a given result / parameter to a given candidate method. It considers the type bounds in the TypeParameter blok (and in the arguments).

Unit test has been added to cover as many situations as possible (positive, and failures).

Hope my contributions are useful. 

Best regards,
Sjaak