Improve handling of leading and trailing spaces in configuration files
Current situation
Configuration parsing is quite strict wrt spaces (in configuration files).
For example the following config entry:
/etc/squashtf/admin_trusted_key.pub, admin, groupe_admin, "admin"
gives value admin
for column 2, groupe_admin
for column 3, and "admin"
for column 4.
Desired outcome
Being able to add leading or trailing spaces in configuration files.