[fix] docs of new form controls

docs/form/api/avatar/avatar_beforechange_event.md

@@ -19,9 +19,9 @@ Return `false` to prevent changing the value of the control; otherwise, `true`.
 
 @example:
 form.getItem("avatar").events.on("beforeChange", value => {
-    return (value.file && value.file?.name?.length > 10) ?? true; 
-    // prevent changes if the name of the uploaded file is 
-    // less than 10 characters including the extension 
+    return value.file && value.file.size <= 2097152;
+    // prevent changes if the size of the uploaded file is
+    // more than 2Mb or the file is empty
 });
 
 @descr:

docs/form/api/avatar/avatar_selectfile_method.md

@@ -12,7 +12,7 @@ description: You can explore the selectFile method of the Avatar control of Form
 
 @example:
 form.getItem("avatar").selectFile(); 
-// -> true/false
+
 
 @descr:
 The type and extension of the selected image depends on the [accept](form/api/avatar/api_avatar_properties.md/#accept) property in the [control's configuration](form/api/avatar/api_avatar_properties.md).

docs/form/api/avatar/avatar_setvalue_method.md

@@ -17,7 +17,7 @@ description: You can explore the setValue method of the Avatar control of Form i
 form.getItem("avatar").setValue([
     {
         "id": "image",
-        "src": "http://domen/upload/files/image.png",
+        "src": "https://server.domain/upload/image.jpg",
         "status": "uploaded"
     }
 ]);

docs/form/api/fieldset/fieldset_foreach_method.md

@@ -6,17 +6,17 @@ description: You can explore the forEach method of the Fieldset control of Form
 
 # forEach()
 
-@short: allows iterating through all the nested elements
+@short: allows iterating through all the nested items
 
 @signature: {'forEach(callback: (item: obj, index: number, array: obj[]) => void, tree?: boolean): void;'}
 
 @params:
 
-- `callback: function` - a function that will iterate over the elements of the fieldset. It is called with the following arguments:
-	- `item: object` - the object of an element (control) 
+- `callback: function` - a function that will iterate over the items of the fieldset. It is called with the following arguments:
+	- `item: object` - the object of an item 
 	- `index: number` - the index of an item
-	- `array: object[]` - an array of iterated elements
-- `tree: boolean` - defines, whether all the nested elements should be iterated, *false* by default
+	- `array: object[]` - an array of iterated items
+- `tree: boolean` - defines, whether all the nested items should be iterated, *false* by default
 
 @example:
 form.getItem("fieldset").forEach((item, index, arr) => {