hdt: Implement aliases

hdt: Implement aliases

Impact: New alias feature; CLi backward compatible

`dmi' is now a shorthand for `set mode dmi' (idem for all modes). This
is performed via a new routine: expand_aliases.

It is now also possible to match aliases (e.g. `q', `quit') to a single
valid command (e.g. `exit'). The list needs to be populated manually and
is intented to be kept short. Eventually, the CLI will support
autocompletion that will help user experience.

Signed-off-by: Pierre-Alexandre Meyer <pierre@mouraf.org>