scalar multiplication fails on RGB24

[hofmannmartin]

Hi folks I am working on ColorVectorSpace Version 0.1.8. If I try to evaluate RGB24(1,0,0)*0.5 I get

ERROR: too many parameters for type RGB24
 in *(::Float64, ::ColorTypes.RGB24) at ColorVectorSpace/src/ColorVectorSpace.jl:114
 in *(::ColorTypes.RGB24, ::Float64) at ColorVectorSpace/src/ColorVectorSpace.jl:134

There seems to be some underlying problem with RBG24 since the same happens for vector addition.