Fix typo in bash completion
Keep arrow level in scripts

Since we use a global variable in installsystems.printer to store the arrow
level, we have to keep this module in scripts global context.
Improve is info command

Add image format display
Add new options
Fix bad handling of changelog with version which are not number.
Rework Image changelog show code

Fix complex number handling in changlog introduced by 78ddf912032.
Split show function in show and show_all
Improve changelog output
Fix arrow indentation in scripts

Reported-by: Aurélien Dunand <aurelien.dunand@smartjog.com>
Fix bad image format field in db addition
Bump image format to 2.0

This introduce the new image format version in X.Y by upgrade from 1 to 2.0.
Where X is an image forward compatibility breaking and Y a revision.

The new format is needed because we move versionning from number to string
Single quote my love
Upgrade is about repository not database

Database should not be exposed to external. We should use repository most of
time.
Handle exit() in scripts

Allow scripts to call exit() or exit(0) to interupt their execution properly.
Can save a useless brace adn tab time.

Exiting another value cause script to fail.