Apply Checkbox style property to internal .check

This will allow you to override the styles of the visible check element
instead of the hidden input element.

This fixes #791.

components/checkbox/Check.js

@@ -2,11 +2,12 @@ import React, { PropTypes } from 'react';
 import classnames from 'classnames';
 
 const factory = (ripple) => {
-  const Check = ({checked, children, onMouseDown, theme}) => (
+  const Check = ({checked, children, onMouseDown, theme, style}) => (
     <div
       data-react-toolbox='check'
       className={classnames(theme.check, { [theme.checked]: checked })}
       onMouseDown={onMouseDown}
+      style={style}
     >
       {children}
     </div>
@@ -19,7 +20,8 @@ const factory = (ripple) => {
     theme: PropTypes.shape({
       check: PropTypes.string,
       checked: PropTypes.string
-    })
+    }),
+    style: PropTypes.object
   };
 
   return ripple(Check);

components/checkbox/Checkbox.js

@@ -47,7 +47,7 @@ const factory = (Check) => {
     }
 
     render () {
-      const { onChange, theme, ...others } = this.props; //eslint-disable-line no-unused-vars
+      const { onChange, theme, style, ...others } = this.props; //eslint-disable-line no-unused-vars
       const className = classnames(theme.field, {
         [theme.disabled]: this.props.disabled
       }, this.props.className);
@@ -66,6 +66,7 @@ const factory = (Check) => {
             checked={this.props.checked}
             disabled={this.props.disabled}
             rippleClassName={theme.ripple}
+            style={style}
             theme={this.props.theme}
           />
           {this.props.label ? <span data-react-toolbox='label' className={theme.text}>{this.props.label}</span> : null}