Add class name attribute into column property.

Author: Tina C Lin (RD-TW)

README.md

@@ -335,6 +335,7 @@ rowKey              | string or Function(record):string | 'key'   | If rowKey is
 
 Name      | Type                 | Default | Description
 :---      | :---                 | :------ | :----------
+className | String               |         | class name of the table cell.
 key       | String               |         | Key of this column.
 title     | React Node           |         | Title of this column.
 dataIndex | String               |         | Display field of the data record.

src/TableCell.jsx

@@ -1,3 +1,4 @@
+import classNames from 'classnames';
 import React, { PureComponent } from 'react';
 import PropTypes from 'prop-types';
 import get from 'lodash.get';
@@ -18,9 +19,15 @@ class TableCell extends PureComponent {
         const { column, record } = this.props;
         const cName = column.dataIndex;
         const render = column.render;
+        const className = column.className;
         let text = get(record, cName);
         return (
-            <div className={styles.td}>
+            <div
+                className={classNames(
+                    className,
+                    styles.td
+                )}
+            >
                 <div className={styles.tdContent}>
                     {
                         render ? render(text, record) : text