Fix R-1830 prop, add two new engines

M-74, Russian radial, essentially an R-1830-94 with a turbo
I-1730,  a higher displacement (and thus more useful and, probably,
workable) "hyper engine." Inverted V, with turbo. Two variants, early
and late, essentially performing like I-1430 was supposed to. (1920HP
with P-47 turbo, 2400HP with 3350-TC or so turbo)