Short term :
------------

General
  - Fix init mode (ah=00). Should use more BIOS variables
  - Add new functionalities and modify static functionality table
  - Performance : 16 bits IO

v0.8
  - Implement the remaining functions (don't know if all are needed):
    - display switch interface ah=12 bl=35
    - video refresh control ah=12 bl=36

v1.0
  - Bugfixes


=================================================================================================
VBE:
----
Long term:
- have text io functions in vbe mode