Readme confusing example

[Ken-B]

The current Readme section on Functions is a bit confusing.
In 1. we get a value of x = 0.7472542331020509, but in 2. the inverse gives z = 0.6543406780096065 and claims x == z.

I find that depending on your luck (or precision), x will not always equal z:

julia> using Random; Random.seed!(42);

julia> x = rand(dist)
0.36888689965963756

julia> y = link(dist, x)
-0.5369949942509267

julia> z = invlink(dist, y)
0.36888689965963756

julia> x==z
true

julia> using Random; Random.seed!(43);

julia> x = rand(dist)
0.3885220158396991

julia> y = link(dist, x)
-0.45352911444046184

julia> z = invlink(dist, y)
0.38852201583969914

julia> x == z
false

Maybe use \approx to show x ≈ z?

[torfjelde]

Good idea; opened a PR to do:) Thanks!