Adding a few methods in motor.cpp to have the distinction between move and moveTo from the Accelstepper librairie. In fact I created same methods using moveTo but using move and I change comments t explin how it works.

I think it would be useful to see later if we are using all these methods
or if some of them can be deleted.

The problem was that i diddn't get the usefulness af the former attribute
retain_accel, which is useful for the use of the limit switch, I change
back the name and rename move_to_mm to move_to_mm_limit_switch and
move_mm to move_to_mm

Now that the first draft of the graphical interface has been completed, it's time to link the syringe and engine code to it.

Every compilation problem have been resolved but the syringe pump does not work with the we interface

Split motor.h into motor.h an motor.cpp, dding a few fuction (some setters missing and conversion) and adding comments.

changing forward_clockwise to _clockwise_equals_forward in motor.h (to fit the way to use it in syringefilled.h)

Changing the name of _retain_accel to _acceleration_mm_per_sec_per_sec in motor class (so it fit better and lt us know t unit)

Ajout d'une fonction booléenne pour savoir si le moteur tourne (dans l'objectif de noter l'état du moteur sur l'interface graphique).