Contains S3 backup

setup tag: setup-matrix-backup

Introduced these configurable variables
matrix_backup_enabled
matrix_backup_bucket
matrix_backup_bucket_endpoint
matrix_backup_bucket_awscli_docker_image_latest
matrix_backup_bucket_key_id
matrix_backup_bucket_key_secret
matrix_backup_rsync_target
matrix_backup_cron_day

Disabled on default
Default cron job will run weekly

Added compatible s3 services
Added simple backup acl
Added awscli utility container
Created environment file
Created one shot systemd service file

Tested matrix-backup/env-backup deployment
Tested matrix-backup cleanup
Tested IAM Role s3 backup access