Auto-detect @Inject method parameter types

[manovotn]

Created as a tracking issue for #172

Test instances are treated as injection targets and as such can declare an initializer and we will invoke it (InjectionTarget#inject).
The annotation-based approach should therefore scan for these methods and automatically register they parameter types as beans.

Furthermore, the existing code seems to scan for methods annotated with @Inject and registers their return type - this is IMO a bug because those methods are either initializers or annotated c-tors neither of which have return types that should interest the auto-Weld extension.