Restored proper handling of varargs in case of unresolvable type variable

Fixed through falling back to the raw parameter type in the TypeDescriptor(MethodParameter) constructor, properly detecting the vararg array even in case of an unresolvable type variable, and through restoring getElementTypeDescriptor's original behavior for arrays, i.e. always returning a non-null descriptor.

Issue: SPR-11494
Relaxed statement on early validation of bean references

Issue: SPR-11495
Upgraded to Hibernate 4.2.10