Update constituent examples and add README

docs/src/examples.md

@@ -61,3 +61,8 @@ showing how the jets merge from their different constituents.
 The `examples/EDM4hep` folder contains examples of using EDM4hep reconstructed
 particles as input to jet reconstruction. See the specific `README.md` file in
 that directory as well as [EDM4hep Inputs](@ref).
+
+## Jet Constituents
+
+The `examples/constituents` folder shows an example of the two mechanisms to
+retrieve jet constituents.

examples/constituents/README.md

@@ -0,0 +1,7 @@
+# Jet Consitituents
+
+The `jetreco-constituents.jl` example shows how to retrieve jet constituents (by
+index and by reference to jet objects).
+
+The `jetreco-constituents-nb.jl` is the same example, just in Pluto notebook
+form.

examples/constituents/jetreco-constituents-nb.jl

@@ -1,5 +1,5 @@
 ### A Pluto.jl notebook ###
-# v0.19.46
+# v0.20.3
 
 using Markdown
 using InteractiveUtils
@@ -23,8 +23,6 @@ Perform a simple reconstruction example and show how to retrieve constituent jet
 
 # ╔═╡ b16f99a0-31ec-4e8f-99c6-7a6fcb16cbee
 md"As this is running in development, use `Pkg` to activate the local development version of the package and use `Revise` to track code changes.
-
-(Currently you must use the `jet-constituents` branch of `JetReconstruction`.)
 "
 
 # ╔═╡ 79f24ec1-a63e-4e96-bd67-49661125be66