Property definitions

ios $ UIStackViewDistribution :: defaultinit
# Defines the size and position of the arranged views along the `UIStackView`'s axis
extern class UIStackViewDistribution in "ObjC" `{ NSInteger `}
	new horizontal in "ObjC" `{ return UILayoutConstraintAxisHorizontal; `}
    new fill in "ObjC" `{ return UIStackViewDistributionFill; `}
    new fill_equally in "ObjC" `{ return UIStackViewDistributionFillEqually; `}
    new fill_proportionally in "ObjC" `{ return UIStackViewDistributionFillProportionally; `}
    new equal_spacing in "ObjC" `{ return UIStackViewDistributionEqualSpacing; `}
    new equal_centering in "ObjC" `{ return UIStackViewDistributionEqualCentering; `}
end
lib/ios/ui/uikit.nit:562,1--570,3