* Fix test invalid prop warning.
Resolved by rewiring Banner to be a string instead of object.
It is an object becaue the test webpack does not use the image loader.

* Fix test propType warning by passing onChange.
This seems to be a debatable issues (1118) with react which requires an onChange if providing a value.

* Fix test warnings by passing required props.

* Increate test coverage of the Img component.

* Update src proptype to stop test warnings