[FIX](SelectRenderer) When trying to clear the value of a property, the value "${p:}" would be shown instead
[FIX](GenericProperty DefaultValue) An empty _DefaultValue_ tag in a property with OutputType _Boolean_ would result in a default value of "true". This messes up CCC properties, in which several boolean properties have no default value on purpose. Fixated the default value of the property _IncludeSolutions_ to true, so that its behavior would not change.