update README

README.md

@@ -4,6 +4,7 @@
 1. [What is MyLabStocks?](#About)
 2. [Documentation](#Documentation)
 	- [Installation](doc/INSTALL.md)
+	- [Upgrading](doc/admin/upgrading/README.md)
 	- [Administrators manual](doc/admin/README.md)
 	- [Guidelines for developers](doc/dev/README.md)
 3. [Features](#Features)
@@ -19,8 +20,9 @@ It was later (in 2019-2021) completely recoded into the Laravel PHP framework in
 
 ## Documentation <a name="Documentation"></a>
 
-- [Installation](doc/INSTALL.md) : detailed instructions on installation procedure. 
-- [Administrators Manual](doc/admin/README.md) : documentation on database structure and administrative tasks such as creating users and accounts, upgrading etc.
+- [Installation](doc/INSTALL.md) : detailed instructions on installation procedure.
+- [Upgrading](doc/admin/upgrading/README.md) : detailed instructions on how to upgrade. 
+- [Administrators Manual](doc/admin/README.md) : documentation on database structure and administrative tasks such as creating users and accounts, performing backups etc.
 - [Guidelines for developers](doc/dev/README.md) : how to contribute to the source code of MyLabStocks.
 
 ## Features  <a name="Features"></a>