RFORCE uses wrong units and direction for rotational acceleration

[victorkemp]

It seems to treat the input as in radian/time**2 instead of revolution/time**2, and with opposite sign.

Affects commit e7c0d1

rotational acceleration = 1.5 rev/time**2
alpha = 2 * pi * rotational acceleration
r     = 2
m     = 7
            (  0  )   ( r )
F     = m * (alpha) x ( 0 )
            (  0  )   ( 0 )
        ( 0                  )
      = ( 0                  )
        (-131.94689145077132 )

Reaction force = -F

Mystran:-2.100000E+01 wrong
Comlab: 1.319469E+02 correct

SOL 101
CEND
SPCFORCES = ALL
LOAD = 1
BEGIN BULK
GRID           1       0     0.0     0.0   0.0         0       3
GRID           2       0     2.0     0.0   0.0         0
CELAS2         1   3.0+6       1       3       2       3
RFORCE         2       0       0     0.0     0.0     1.0     0.0        +
+            1.5
CONM2          2       2       0     7.0
LOAD           1     1.0     1.0       2
ENDDATA