
o [domi] Update compute so that a built-in value can also be computed. This
   is required to fix a bug is sshd_config where match element values
   are needlessly written to files

o [domi] Filter element according to element in SimpleUI and TERMUI



* Rework backends:

- obsolete custom backend

- move cds backend in C::M::Backend::Any child class

- move perl backend in C::M::Backend::Any child class

- Use the same backend object to read and write files
   This need to move most parameters of read/write to object attributes

- Migrate file handling to Path::Tiny

