More realistic countermeasures management

[Lixma 06]

The current kneeboard counter is unrealistic (and looks a bit War Thunder)

So here's an idea to improve the realism and aesthetics!

This addition to the AI GUI more closely follows the layout of Petrovich's countermeasures control unit, and indicates remaining stores by active/expended cassettes instead of individual flare/chaff cartridges - much more realistic.

[Raffi75]

+1