Conical grain type can only have 'Both' inhibited ends option

On line 20 of conical.py only 'Both' option is listed for the inhibitedEnds property array, leading to the UI only being able to select this.

openMotor/motorlib/grains/conical.py

Line 20 in 9e4d6fd

self.props['inhibitedEnds'] = EnumProperty('Inhibited ends', ['Both'])

However in the rest of the code there appears to be sufficient code to calculate the burning for all 4 types (Both, Neither, Top, Bottom), e.g.

openMotor/motorlib/grains/conical.py

Line 89 in 9e4d6fd

if self.props['inhibitedEnds'].getValue() in ['Neither', 'Bottom']:

Sorry for the delay! There was some bug with calculating the regression of uninhibited conical grains, so I disabled them temporarily to get the rest of the release out. I would like to fix this, so I'll mark this as a bug to remind myself.