hope to support Vector{Tuple}！

[13299118606]

I hope to support tuple methods, because tuple vectors are very efficient in Julia. In many cases, tuple vectors Vector{Tuple{Float64, Float64, Float64}} are used instead of Vector{Vector{Float64}}, but errors occur when saving tuples

matwrite("matfile.mat", Dict("tu"=>(1,2,3)))

matwrite("matfile.mat", Dict("tu"=>(1,2,3)))
ERROR: This is the write function for CompositeKind, but the input doesn't fit