Update README.md (#308)

Author: Cygra

README.md

@@ -58,7 +58,7 @@ import List from 'rc-virtual-list';
 | data       | Data list                                               | Array                                                                                                                                                                                 | -       |
 | disabled   | Disable scroll check. Usually used on animation control | boolean                                                                                                                                                                               | false   |
 | height     | List height                                             | number                                                                                                                                                                                | -       |
-| itemHeight | Item minium height                                      | number                                                                                                                                                                                | -       |
+| itemHeight | Item minimum height                                     | number                                                                                                                                                                                | -       |
 | itemKey    | Match key with item                                     | string                                                                                                                                                                                | -       |
 | styles     | style                                                   | { horizontalScrollBar?: React.CSSProperties; horizontalScrollBarThumb?: React.CSSProperties; verticalScrollBar?: React.CSSProperties; verticalScrollBarThumb?: React.CSSProperties; } | -       |