Flesh out contrib python dep installation instructions and add Nix se…

…ction

contrib/README.md

@@ -2,21 +2,49 @@
 
 ## Installing
 
+There are two ways to install the requirements:
+- poetry
+- nix
+
+### Poetry
+There are two ways to install poetry:
+- pipx
+- official installer
+
+#### Pipx
+
 ```
 # Install pipx
 sudo apt update
 sudo apt install pipx
+pipx install poetry
+```
 
+#### [Or, click here for the official installer](https://python-poetry.org/docs/#installing-with-the-official-installer)
+
+Once poetry is installed, install the Python dependencies:
+
+```
 # The following commands need to be run as the user who will be running
 # the clboss utility commands (connecting to the CLN RPC port)
 
-# Install poetry: https://python-poetry.org/docs/#installing-with-the-official-installer
-
 # Install clboss contrib utilities
 poetry shell
 poetry install
 ```
 
+### Nix
+If you have nix, you can just do, from the project root:
+```
+nix-shell contrib-shell.nix
+```
+
+Then before running the commands below, be sure to do:
+
+```
+cd contrib/
+```
+
 ## Running
 
 ```