Update readme (#75)

* Update readme

* Update ADMIN.md

ADMIN.md

@@ -1,3 +1,38 @@
 # Admin panel documentation
 
-Coming soon documentation on this package
+This package is an extension of the [Template package](https://github.com/EscolaLMS/Templates/blob/main/ADMIN.md) and is used for managing email templates.
+
+Templates are defined in the *Templates* and *Email* tabs. From the template list, you can create, edit or delete a template.
+
+![Templates](https://github.com/EscolaLMS/Templates-Email/assets/59456825/c317bc59-4d20-4307-9f58-5301cb5985ca)
+
+Each email template has a name, an event, and you can set the template to be the default.
+Sending an email is only possible for the default template.
+The list of events available for selection may vary depending on the installed *escolalms* packages. Each package emits its own events.
+
+![Template form](https://github.com/EscolaLMS/Templates-Email/assets/59456825/30b51f09-4271-4911-a9aa-4fcf955cb330)
+
+Clicking the *Preview* button will send an email to you. The values of the variables will be mocked.
+
+![Preview](https://github.com/EscolaLMS/Templates-Email/assets/59456825/27042b6a-0d9e-4e05-b3d9-4b6b0e1a1797)
+
+When defining a template, you have variables to use. There are two types of variables global and event-defined. Global variables store general, system-related information, personalized variables store information directly related to the event.
+Variables use a convention, with the @ sign before the variable name, to use a variable in a template you need to put the @ sign and the variable name, e.g. @VarSimpleName. 
+
+![Variables](https://github.com/EscolaLMS/Templates-Email/assets/59456825/751d01f5-7448-47bd-b77c-836f5f699174)
+
+The variables that are in the *required variables* section are the ones you must use in your template.
+
+![Required variables](https://github.com/EscolaLMS/Templates-Email/assets/59456825/8d8d5282-b74f-4540-883a-67fb3fb250a2)
+
+Mjml is used to create the content of an email.
+
+![Email content](https://github.com/EscolaLMS/Templates-Email/assets/59456825/bc67ee9b-e415-4bb9-8df6-b979daa95b8d)
+
+You can use *Settings* to save recurring parts of the template, e.g. footer or header.  
+Just define new variables in the *mail* group with the mjml code and then use those variables in the template.
+
+![Global mail variables](https://github.com/EscolaLMS/Templates-Email/assets/59456825/adb8a588-f3fd-469c-8ed8-fb8667eef776)
+
+![Content with global variables](https://github.com/EscolaLMS/Templates-Email/assets/59456825/4f69fcfe-7a26-40b5-8e03-a3ae2b0b1cd3)
+

README.md

@@ -44,30 +44,10 @@ Each notification is created as a class describing available variables that can
 
 ## Tests
 
-Run `./vendor/bin/phpunit --filter 'EscolaLms\\TemplatesEmail\\Tests'` to run tests. See [tests](tests) folder as it contains a basic implementation of Variable (or Template description) class with minimal customisation - a quite good starting point for creating your own.
+Run `./vendor/bin/phpunit --filter 'EscolaLms\\TemplatesEmail\\Tests'` to run tests. See [tests](https://github.com/EscolaLMS/Templates-Email/tree/main/tests) folder as it contains a basic implementation of Variable (or Template description) class with minimal customisation - a quite good starting point for creating your own.
 
 Test details [![codecov](https://codecov.io/gh/EscolaLMS/Templates-Email/branch/main/graph/badge.svg?token=O91FHNKI6R)](https://codecov.io/gh/EscolaLMS/Templates-Email) [![Tests PHPUnit in environments](https://github.com/EscolaLMS/Templates-Email/actions/workflows/test.yml/badge.svg)](https://github.com/EscolaLMS/Templates-Email/actions/workflows/test.yml)
 
-## Usage on front end
-
-### Admin panel
-
-#### **Left menu**
-
-![Menu](docs/menu.png "Menu")
-
-#### **List of templates**
-
-![List of templates](docs/list.png "List of templates")
-
-#### **Creating/editing template**
-
-![Creating/editing template](docs/edit.png "Creating or editing template")
-
 ## Permissions
 
 No Permissions defined for this package.
-
-## Roadmap. Todo. Troubleshooting
-
-- ???