- Bump version: 10.1.14 → 10.1.15

- Fixed sphinx_rtd_theme setup
Delete obsolete display_version attribute

- Evaluate eficsm everywhere
Fixed _supports_bios_modules() to take an eventually
provided eficsm setup into account. The grub config still
searches for i386 grub modules even if eficsm="false"
is set.

- Fixed debian bootstrap script calls
Run scripts as commands with their native shebang and not
through bash. Not all debian package scripts uses bash, some
of them uses sh which can be a link to dash or other
interpreters. This Fixes #2660

- Update TW integration tests
The package x86info was dropped from TW

- Turn DiskFormat into an ordinary class
- it does not need to be an abstract base class
- use f-strings where applicable instead of format()
- change return type of _custom_args_for_format from list to tuple

- Add new containers section
Allow to specify references to OCI containers in the
image description like in the following example: