tiny feature request: GeometricShifted

[alanedelman]

the shifted geometric distribution
(left column in https://en.wikipedia.org/wiki/Geometric_distribution)

[mauricelanghinrichs]

If I'm not mistaken this can be currently achieved by

using Distributions
GeometricShifted(p) = Geometric(p) + 1

# some tests
p = 0.7
mean(GeometricShifted(p)) ≈ 1/p # true
var(GeometricShifted(p)) ≈ (1-p)/p^2 # true
pdf(GeometricShifted(p), 0) ≈ 0 # true
all(pdf(GeometricShifted(p), k) ≈ (1-p)^(k-1)*p for k in 1:100) # true

but I agree, would be nice to have this as a convenience method.