Since the addition of `set -e`, several parts of the script became dead code.

This allows much better understanding for long running Kedifa processes.

also cleanup old unused versions

- Upgrade PHP to version 7.3 and add more  required extensions
- Use mariadb from stack/erp5 because we won't code again all feature done there for mariadb, initialization and backup to have it up-to-date.
- Delete old files which are not used anymore
- Remove integrated resilience scripts, resilience will works with webrunner which is more stable today.
- Add Nextcloud software release with some script for auto configuration.

/reviewed-on nexedi/slapos!602

   It prevents things skip offline control.

This repository for holding the BT which not suitable to put
in erp5 main repository

Include *.data and *.wasm files.
Which the content type is "application/wasm"