React v15.5 update causes breaking changes

[shammamah-zz]

PropTypes must now be imported from the prop-types package, as mentioned in the React v15.5 announcement: https://reactjs.org/blog/2017/04/07/react-v15.5.0.html

From the announcement:

Prop types are a feature for runtime validation of props during development. We’ve extracted the built-in prop types to a separate package to reflect the fact that not everybody uses them.
In 15.5, instead of accessing PropTypes from the main React object, install the prop-types package and import them from there:

React.PropTypes is used here:

molecule-3d-for-react/src/components/molecule_3d.jsx

Line 53 in ea30999

selectedAtomIds: React.PropTypes.arrayOf(React.PropTypes.number),