Allow CardMedia to have flexible height per documentation
Allow CardMedia to have flexible height per documentation

The documentation for CardMedia specifies that if the `aspectRatio`
property is not set, the media will have a flexible height.  The
existing implementation did not provide this, and would instead always
render with a height of `0`, effectively hiding the element.

This change should bring the component into line with the documentation.

rubenmoya/react-toolbox,react-toolbox/react-toolbox,showings/react-toolbox,KerenChandran/react-toolbox,rubenmoya/react-toolbox,rubenmoya/react-toolbox,jasonleibowitz/react-toolbox,react-toolbox/react-toolbox,react-toolbox/react-toolbox,soyjavi/react-toolbox,soyjavi/react-toolbox,jasonleibowitz/react-toolbox,showings/react-toolbox,KerenChandran/react-toolbox