Rewrite readme with installation and requirements

To give new contributers a better understanding of how to get started on the code, it would be nice if extra **requirements** and **installation** instructions are added to the readme file.

**Note:** we are accepting multiple pull requests to the readme file, since we feel it is important that the readme is as clear as can be to new users. If you think anything is missing or could use clarification, feel free to open a PR.

### Requirements
Since the project is built in Laravel, requirements would be
- Laravel
- Composer
- NPM
But it is also necessary to have a mysql database up and running.

These requirements should be added including links to pages explaining how to install and use them.

### Installation
Aditionally, the installation section needs to be checked to verify wheter all necessary steps to get the application up and running are included.