New literate functionality

Thanks to this PR, it should be possible to have post-specific environments, which should make Literate.jl-based posts easier...

Let's see if it works:

using CairoMakie
using Distributions

d = Normal(0, 0.5)

Distributions.Normal{Float64}(μ=0.0, σ=0.5)

fig = Figure()
for i in 1:4
    ax = Axis(fig[
        ceil(Int, i / 2), # 1,1,2,2
        2 - i % 2]; # 1,2,1,2
        xlabel = "10^$i samples"
    )

    lines!(ax, (d))
    hist!(ax, rand(d, 10^i))
end

fig