IHF: format_bytes doc added.

Author: dmitry-ivanov

README.md

@@ -23,6 +23,9 @@ Provides Laravel-specific and pure PHP helper functions.
 - [Dump](#dump)
     - [get_dump](#get_dump)
 
+- [Format](#format)
+    - [format_bytes](#format_bytes)
+
 - [Json](#json)
     - [is_json](#is_json)
 
@@ -55,6 +58,17 @@ $dump = get_dump($var);
 // ]
 ```
 
+## Format
+
+#### `format_bytes()`
+
+Formats bytes into kilobytes, megabytes, gigabytes or terabytes, with specified precision:
+```php
+$formatted = format_bytes(3333333);
+
+// 3.18 MB
+```
+
 ## Json
 
 #### `is_json()`