Do not declare isReactComponent

Fixes #8

With the React 16.5.0 release, this component's use of isReactComponent breaks React's shouldConstruct check. Here is a more detailed explanation of the problem: facebook/react#13580

Support Function as Child Component

Release Notes

• Please see readme for details
• Special thanks to @ElGrecode for suggesting this feature!

Support React 16

Release Notes

Support React 16
Upgrade dependencies
Bug fix: If child component renders null react-hover-observer throws exception

Support React 15.5 and New Defaults

Notes

• Support React 15.5
• onMouseEnter prop now defaults to setting isHovering
• onMouseLeave prop now defaults to unsetting isHovering
• Four new editable examples hosted on CodePen
• Test coverage monitored by Coveralls
• Package now includes CommonJS, ES6, and UMD modules
• Upgrade dependencies