Some refinements to the Menu infraestructure (#962)

* Correct definition of btrfs standard layout

* Solve issue #936

* make ask_for_a_timezone as synonym to ask_timezone

* Some refining in GeneralMenu
secret is now a general function

* Revert "Some refining in GeneralMenu"

This reverts commit e6e131cb19795e0ddc169e897ae4df57a1c7f9fb.

* New version of the FlexibleMenu
* Added new functionality to Selector
* Created a GeneralMenu class
* GlobalMenu is made a child of GeneralMenu

* Some refining in GeneralMenu
secret is now a general function

* log is invoked in GeneralMenu directly

* Materialize again _setup_selection_menu_options. Gives more room to play

* Callbacks converted as methods
Synch() (data area and menu) decoupled from enable()
and made general before any run

* Only_hd gets a new implementation of the menu
flake8 corrections

* New version of the FlexibleMenu
* Added new functionality to Selector
* Created a GeneralMenu class
* GlobalMenu is made a child of GeneralMenu

* changes from the rebase left dangling

* Adapt to PR #874

* Adapted to nationalization framework (PR 893).
String still NOT adapted

* flake8 complains

* Use of archinstall.output_config instead of local copy at swiss.py

* Problems with the last merge

* git complains

* Menu admits now preset values and cursor positioning

* Now GeneralMenu moves to the next entry after each selection

* flake8 complains

* Control of limits for cursor position at GeneralMenu

* Make auto cursor positioning optional at GeneralMenu.
True for GlobalMenu

* Code cleanup after rebase, and flake8 complains

1 files changed, 1 insertions, 0 deletions

diff --git a/examples/only_hd.py b/examples/only_hd.py
index c0364cd1..5d081b14 100644
--- a/examples/only_hd.py
+++ b/examples/only_hd.py
@@ -1,3 +1,4 @@
+
 import logging
 import os
 import pathlib