Allow for more than one stall AOA

At the moment, there is only one stall AOA modelled in the current flight
model and it is defined as the alpha where maximum value of Cl is reached in
the lift_coef_aoa_table. However, the stall AOA changes with various
variables, notably the Mach number and it could be great to have a table
allowing to tune it for different Mach numbers, by scaling it up or down, in
the same way the lift coefficient can be tuned via the lift_coef_mach_table.