Fix certbot-nginx-ssl issues and improved installer script

[MarcOverIP]

This PR:

• Fixes the initialisation of the init-letsencrypt.sh script to better work when you are not using Letsencrypt
• Adds parameters to the init-letsencrypt.sh script for domain and docker-compose file
• Adds the config.json parameter enable_letsencrypt (boolean) that is used in the installer
• Modifies install-elkserver.sh to include aforementioned changes
• Adds extra parameter fixedmemory to install-elkserver.sh to hardcode memory for neo4j and es (great for testing on virtual machines)
• fixes docker-compose files to adhere to naming standard of containers
• fixes a bug when .env existed a new password for elastic user was generated
• Reformats the setup and printing of info of the install-elkserver.sh script
• Clean-ups the scripts