Julia 0.4 compat when using JuMP. Fixes dcjones/Gadfly.jl#598.
Julia 0.4 compat when using JuMP. Fixes dcjones/Gadfly.jl#598.

yuyichao/Compose.jl,darwindarak/Compose.jl,JuliaPackageMirrors/Compose.jl,rened/Compose.jl,tkelman/Compose.jl,dcjones/Compose.jl,jiahao/Compose.jl,Hydrotoast/Compose.jl