Use correct vector space definitions

- Undefines errorneous +, * on LCHUv
- Defines +, * on XYZ as a linear vector space
- Defines +, * on all other ColorValues using intermediate arithmetic in
  XYZ space

src/colormaps.jl

@@ -86,11 +86,6 @@ distinguishable_colors(n::Integer; kwargs...) = distinguishable_colors(n, Array(
                                 cs::Vector{Float64},
                                 hs::Vector{Float64})    distinguishable_colors(n, [seed], transform = transform, lchoices = ls, cchoices = cs, hchoices = hs)
 
-
-# Small definitions to make color computations more clear
-+(x::LCHuv, y::LCHuv) = LCHuv(x.l+y.l,x.c+y.c,x.h+y.h)
-*(x::Real, y::LCHuv) = LCHuv(x*y.l,x*y.c,x*y.h)
-
 # Sequential palette
 # ----------------------
 # Sequential_palette implements the color palette creation technique by

src/colorspaces.jl

@@ -295,3 +295,19 @@ const CVconcrete = (HSV, HSL, XYZ, xyY, Lab, Luv, LCHab, LCHuv, DIN99, DIN99d, D
 const CVparametric = tuple(RGB, CVconcrete...)
 const CVfractional = (RGB, XYZ)
 const CVfloatingpoint = (HSV, HSL, xyY, Lab, Luv, LCHab, LCHuv, DIN99, DIN99d, DIN99o, LMS)
+
+# Vector space operations
+import Base: +, *
+
+#XYZ is a linear vector space
++{T}(a::XYZ{T}, b::XYZ{T}) = XYZ(a.x+b.x, a.y+b.y, a.z+b.z)
+*{T}(c::T, a::XYZ{T}) = XYZ(c*a.x, c*a.y, c*a.z)
+function *{S<:Real,T<:Real}(c::S, a::ColorValue{T})
+    U = promote_type(S,T)
+    convert(U,c) * convert(XYZ{U},a)
+end
+
+#Most of the rest aren't, so do the arithmetic in XYZ and convert back
++{T}(a::ColorValue{T}, b::ColorValue{T}) = convert(ColorValue{T}, convert(XYZ{T}, a) + convert(XYZ{T}, b))
+*{T}(c::T, a::ColorValue{T}) = convert(ColorValue{T}, c * convert(XYZ{T}, a))
+