Fix invalid tag

Babel's react-jsx preset treats low-case tags as
literal elements, not as a variables.

So, for jsx:
<wrapper ... />
It generates js:
React.createElement('wrapper')

But we want:
React.createElement(wrapper)

Changing case of variable fixes the issue

Author: huumanoid

src/index.js

@@ -433,21 +433,21 @@ 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 = ReactTooltip.supportedWrappers[this.props.wrapper]
+    if (!Wrapper) Wrapper = ReactTooltip.supportedWrappers['div']
 
     if (html) {
       return (
-        <wrapper className={`${tooltipClass} ${extraClass}`}
+        <Wrapper className={`${tooltipClass} ${extraClass}`}
           {...ariaProps}
           data-id='tooltip'
-          dangerouslySetInnerHTML={{__html: placeholder}}></wrapper>
+          dangerouslySetInnerHTML={{__html: placeholder}}/>
       )
     } else {
       return (
-        <wrapper className={`${tooltipClass} ${extraClass}`}
+        <Wrapper className={`${tooltipClass} ${extraClass}`}
           {...ariaProps}
-          data-id='tooltip'>{placeholder}</wrapper>
+          data-id='tooltip'>{placeholder}</Wrapper>
       )
     }
   }