docs(toJSON): add example to toJSON method

Author: blond

README.md

@@ -270,7 +270,7 @@ buttonTextBoldName.belongsTo(buttonName);     // false
 
 ### valueOf()
 
-Returns object representing the entity name.
+Returns normalized object representing the entity name.
 
 ```js
 const BemEntityName = require('@bem/entity-name');
@@ -283,7 +283,15 @@ name.valueOf();
 
 ### toJSON()
 
-Returns object for `JSON.stringify()` purposes.
+Returns raw data for `JSON.stringify()` purposes.
+
+```js
+const BemEntityName = require('@bem/entity-name');
+
+const name = new BemEntityName({ block: 'input', mod: 'available' });
+
+JSON.stringify(name); // {"block":"input","mod":{"name":"available","val":true}}
+```
 
 ### toString()
 

lib/entity-name.js

@@ -284,7 +284,7 @@ class BemEntityName {
     }
 
     /**
-     * Returns object representing the entity name. Is needed for debug in Node.js.
+     * Returns normalized object representing the entity name.
      *
      * In some browsers `console.log()` calls `valueOf()` on each argument.
      * This method will be called to get custom string representation of the object.
@@ -305,7 +305,14 @@ class BemEntityName {
     valueOf() { return this._data; }
 
     /**
-     * Return raw data for `JSON.stringify()`.
+     * Returns raw data for `JSON.stringify()` purposes.
+     *
+     * @example
+     * const BemEntityName = require('@bem/entity-name');
+     *
+     * const name = new BemEntityName({ block: 'input', mod: 'available' });
+     *
+     * JSON.stringify(name); // {"block":"input","mod":{"name":"available","val":true}}
      *
      * @returns {BemSDK.EntityName.StrictRepresentation}
      */