High-contrast Plus42 skins

[Thomas Okken]

That is to say, instead of

Key: 1 [...]
Key: 2 [...]
Key: 3 [...]
Key: 4 [...]
Key: 5 [...]
Key: 6 [...]

use

Key: 50,51 [...]
Key: 52,53 [...]
Key: 54,55 [...]
Key: 56,57 [...]
Key: 58,59 [...]
Key: 60,61 [...]

Macro: 50 "Σ+"
Macro: 51 "Σ-"
Macro: 52 "1/X"
Macro: 53 "Y^X"
Macro: 54 "SQRT"
Macro: 55 "X^2"
Macro: 56 "LOG"
Macro: 57 "10^X"
Macro: 58 "LN"
Macro: 59 "E^X"
Macro: 60 "XEQ"
Macro: 61 "GTO"