Utilize ByteBuddy's InjectionClassLoader instead of AbstractTypeMaterializer.MyClassLoader

ByteBuddy is able to either wrap or inject defined classes to given classloader whereas MyClassLoader is merely a wrapper. The injection approach would reduce end-user's stack of classloaders by eliminating the need for yet-another classloader.

In #62 I suggested that non-shaded version would be provided because then I could construct the materializer using a non-sealed InjectionClassLoader that contains some custom made abstract classes that I have crafted using ByteBuddy. For those using the shaded the approach would be the more familiar classloader wrapping. For me to start calling the shaded version of ByteBuddy would be rather cumbersome.