feat: add className prop

Resolves mac-s-g#247

Author: j-m

README.md

@@ -43,6 +43,7 @@ Name|Type|Default|Description
 `src`|`JSON Object`|None|This property contains your input JSON
 `name`|`string` or `false`|"root"|Contains the name of your root node.  Use `null` or `false` for no name.
 `theme`|`string`|"rjv-default"|RJV supports base-16 themes.  Check out the list of supported themes [in the demo](https://mac-s-g.github.io/react-json-view/demo/dist/). A custom "rjv-default" theme applies by default.
+`className`|`string`|`undefined`|Additional `className` string to append to the `className` of react-json-view's container.  
 `style`|`object`|`{}`|Style attributes for react-json-view container.  Explicit style attributes will override attributes provided by a theme.
 `iconStyle`|`string`|"circle"| Style of expand/collapse icons.  Accepted values are "circle", triangle" or "square".
 `indentWidth`|`integer`|4|Set the indent-width for nested objects

index.d.ts

@@ -20,6 +20,12 @@ export interface ReactJsonViewProps {
    * Default: "rjv-default"
    */
   theme?: ThemeKeys | ThemeObject;
+  /**
+   * Additional `className` string to append to the `className` of react-json-view's container.
+   *
+   * Default: undefined
+   */
+   className?: string;
   /**
    * Style attributes for react-json-view container.
    * Explicit style attributes will override attributes provided by a theme.

src/js/index.js

@@ -53,6 +53,7 @@ class ReactJsonView extends React.PureComponent {
         onAdd: false,
         onSelect: false,
         iconStyle: 'triangle',
+        className: undefined,
         style: {},
         validationMessage: 'Validation Error',
         defaultValue: null,
@@ -168,11 +169,11 @@ class ReactJsonView extends React.PureComponent {
             name
         } = this.state;
 
-        const { style, defaultValue } = this.props;
+        const { className, style, defaultValue } = this.props;
 
         return (
             <div
-                class="react-json-view"
+                className={"react-json-view" + (className ? " " + className : "")}
                 style={{ ...Theme(theme, 'app-container').style, ...style }}
             >
                 <ValidationFailure