add reference to dev docs

Author: ArnoStrouwen

README.md

@@ -23,7 +23,10 @@ JumpProcesses is a component package in the [SciML](https://sciml.ai/) ecosystem
 and one of the core solver libraries included in
 [DifferentialEquations.jl](https://github.com/JuliaDiffEq/DifferentialEquations.jl).
 
-The documentation includes
+For information on using the package,
+[see the stable documentation](http://jump.sciml.ai/stable/). Use the
+[in-development documentation](http://jump.sciml.ai/dev/) for the version of
+the documentation, which contains the unreleased features. This documentation includes
 - [a tutorial on simulating basic Poisson processes](https://jump.sciml.ai/stable/tutorials/simple_poisson_process/)
 - [a tutorial and details on using JumpProcesses to simulate jump processes via SSAs (i.e. Gillespie methods)](https://jump.sciml.ai/stable/tutorials/discrete_stochastic_example/),
 - [a tutorial on simulating jump-diffusion processes](https://jump.sciml.ai/stable/tutorials/jump_diffusion/),