Fix evaluated Wrapper type

React.createElement expects string or React.Component in first
argument.

React.DOM.div and React.DOM.span are neither strings nor Components.
They are wrappers around React.createElement.
Also, they are deprecated.

Read more:
https://facebook.github.io/react/docs/react-api.html#createelement

For our case, we could safely pass strings to React.createElement,
so, no need to use React.DOM.div etc

Author: huumanoid

src/index.js

@@ -58,10 +58,7 @@ class ReactTooltip extends Component {
     wrapper: 'div'
   };
 
-  static supportedWrappers = {
-    'div': React.DOM.div,
-    'span': React.DOM.span
-  };
+  static supportedWrappers = ['div', 'span'];
 
   constructor (props) {
     super(props)
@@ -433,8 +430,10 @@ class ReactTooltip extends Component {
       {'type-light': this.state.type === 'light'}
     )
 
-    let Wrapper = ReactTooltip.supportedWrappers[this.props.wrapper]
-    if (!Wrapper) Wrapper = ReactTooltip.supportedWrappers['div']
+    let Wrapper = this.props.wrapper
+    if (ReactTooltip.supportedWrappers.indexOf(Wrapper) < 0) {
+      Wrapper = 'div'
+    }
 
     if (html) {
       return (