Update README

Author: Carlgo11

README.md

@@ -1,16 +1,31 @@
 # TempFiles Backend
 [![GitHub Workflow Status](https://img.shields.io/github/workflow/status/Carlgo11/Tempfiles-backend/Test%20PHPUnit?style=for-the-badge)](https://github.com/Carlgo11/Tempfiles-backend/actions)
+[![GitHub](https://img.shields.io/github/license/carlgo11/tempfiles-backend?style=for-the-badge)](https://github.com/Carlgo11/TempFiles-backend/blob/master/LICENSE)
+[![GitHub release (latest SemVer)](https://img.shields.io/github/v/release/carlgo11/tempfiles-backend?style=for-the-badge)](https://github.com/Carlgo11/TempFiles-backend/releases)
 
 ## API calls :mega:
 A list of available API calls can be found over at [Postman](https://documenter.getpostman.com/view/1675224/SW7ezkZn).
 
-## Local installation :desktop_computer:
+## Contributing :writing_hand:
 
-1. Install PHP, Nginx, Git
+To edit the TempFiles-Backend code you need:
+* An IDE/Editor that supports [EditorConfig](https://editorconfig.org/#download).
+* Composer
+* PHP 7.2 (Or later)
+* PHP extensions: curl, xsl, mbstring
+
+To install all dependencies, run the following command:
+```BASH
+composer install
+```
+
+## Deployment :desktop_computer:
+
+1. Install PHP, Nginx, Git, Composer
    ```BASH
    sudo apt update
    sudo apt upgrade
-   sudo apt install nginx php php-fpm php-curl php-mbstring git
+   sudo apt install nginx php php-fpm composer php-curl php-mbstring git
    ```
 
 2. Download the source code
@@ -19,7 +34,12 @@ A list of available API calls can be found over at [Postman](https://documenter.
    cd Tempfiles-backend/
    ```
 
-3. Set file path
+3. Download dependencies
+   ```BASH
+   composer install --no-dev
+   ```
+
+4. Set file path
    ```BASH
    nano src/com/carlgo11/tempfiles/config.php
    ```
@@ -30,12 +50,12 @@ A list of available API calls can be found over at [Postman](https://documenter.
    chmod 0700 /tempfiles -R
    ```
 
-4. Copy the Nginx configurations to the sites-available directory.
+5. Copy the Nginx configurations to the sites-available directory.
    ```BASH
    cp ./ressouces/nginx/*.conf > /etc/nginx/sites-available/
    ```
 
-5. Generate certificates.
+6. Generate certificates.  
    For HTTPS to work you'll need a certificate. Due to the many different certificate companies and their different ways of generating certificates I won't go into that in this text.
    When you have a certificate, change the following lines in both nginx configs:
    ```BASH
@@ -46,7 +66,7 @@ A list of available API calls can be found over at [Postman](https://documenter.
    ssl_certificate_key {path_to_key}/privkey.pem; #Change path
    ```
 
-6. Restart Nginx
+7. Restart Nginx
    ```BASH
    sudo systemctl restart nginx
    ```