code: public static <T> InjectionProvider<T> providerForQualifiedInstance(final Class<? extends Annotation> qualifier, final T instance) {
          return new QualifiedInstanceInjectionProvider<T>(qualifier, instance);
      }
docs: InjectionProvider that provides a singleton instance of type T for every
  injection point that is annotated with the given qualifier.
  
  @param qualifier
  qualifying annotation of injection point
  @param instance
  the instance to return whenever needed
  @return InjectionProvider for instance